I used to work with tungsten carbide cubes during my PhD thesis. They're used in multianvil high-pressure synthesis. With the right setup you can reach almost 20 GPa of pressure. Not as much as with diamond anvil cells, but you have more reasonable sample sizes (a few milligrams). And thats still like the pressure pretty deep into Earth's mantle.

I also used the opportunity to snap a neat picture of a polished WC cube: https://imgur.com/C2YiMqb.jpg

I always had fun handing them over to students because everyone is surprised by the sheer weight of these things.

Tungsten carbide is actually quite dangerous after it has been subjected to a lot of stress (Such as being stuck into a 1000 t press for a high-pressure synthesis). They have the mean tendecy to explode into super sharp pieces when you're not expecting it, so wear goggles.

FYI, tungsten carbide (tungsten + carbon) is a different substance from the pure metal tungsten... They have very different physical properties.

But I do appreciate your story about tungsten carbide, too :-)

> FYI

I'd wager they're fully aware of the differences between tungsten carbide and pure tungsten, having done a doctorate about it.

The FYI might be poor phrasing, but GP is right that many people confuse the two. This isn't helped by many sellers of novelty "tungsten" online selling tungsten carbide and mentioning it in the fine print, if at all.

If anyone knows where to get a tungsten cube I would be interested. I’ve wanted one since reading this post a few years ago but every vendor usually sells alloys.

This vendor sells cubes of various sizes that they claim to be 99.95% tungsten - https://luciteria.com/metal-cubes/tungsten-cube. I have one of the 1cc cubes and it seems to be of good quality. They also sell a lot of other exotic elements.

Perfect, thank you! Looking it seems they both have a kilo of pure tungsten in cube form measuring 38.1mm^3 or a kilo of tungsten carbide measuring 40mm^3.

I honestly wouldn't have noticed that the Midwest Tungsten Service products weren't pure tungsten, but when I went back to the amazon page, I found a note from the seller:

>The tungsten sphere is 90% tungsten with nickel/iron for the remainder, the aluminum sphere is 6061 alloy.

This actually seems to apply to most of their products. Not just the spheres.

If you search Amazon for "pure tungsten", you'll find vendors selling cubes that are at least more pure than this vendor's stuff. There are also other items that claim to be high purity tungsten.

Can't blame them for selling alloy. Pure tungsten is extremely brittle and virtually unmachineable. So they'll sell you nickel alloy, because you can work that to tolerance. No powder metallurgy required.

Aliexpress, with the usual gamble as to what you actually receive :)

https://www.aliexpress.com/wholesale?catId=0&initiative_id=S...

> They have the mean tendecy to explode into super sharp pieces when you're not expecting it, so wear goggles.

Well, I guess I need to buy a new wedding ring at some point.

Your marriage yields the equivalent of 1000t pressure stress on your wedding ring?

Mine does

Mine did

I accidentally dropped my tungsten carbide wedding band on my kitchen tile floor. Now, I have 4 shattered pieces of tungsten carbide sitting in a box on my desk.

Sounds like the start to an epic quest.

The four shards must be reunited for the prophecy to be fulfilled!

Given that my wedding ring is permanently egg shaped due to some impact that I don't even remember, I'll stick with gold.

Mine too, but mine got deformed when I held my fingers behind a plank I was mounting to a concrete wall using a power screw driver, and didn't engage my brain safety-wise.

Sounds like a good night!

i read something about a guy shattering his tungsten wedding band on his wedding night, after deciding that slapping his hands on concrete was how you're supposed to dance.

professional advice: don't use an exotic metal for your wedding band. some fire departments can't cut it if your ring finger swells up.

Apparently you can shatter tungsten rings with a strong pair of locking pliers. See this amazing medical journal article in which "the Internet was consulted which led to a YouTube video": https://www.hindawi.com/journals/criem/2016/8164524/

Or you could just not wear rings at all. I'm an EMT and the only trauma injury that gives me the creeps is degloving. Happens e.g. when somebody falls off a ladder and their ring gets caught on a nail on the way down. Don't google it.

Many years ago I was told about a British Post Office training film from the days when they were responsible for the telephone system.

A technician climbed a telegraph pole without proper equipment and wearing a ring. He and slipped and tore off the finger wearing the ring. The way it was described to me was horrific, the tendons were pulled out of his hand as well.

I've never seen it so I don't know for sure if it really was like that but the description alone was sufficient for me and I always remove my rings when doing anything like that.

Or wear a silicone one. They are cheap to replace and (in theory) will break if they catch on something. I have a couple from SafeRingz[1] (not affiliated), but there are plenty of cheaper ones on Amazon.

[1]: https://www.saferingz.com/

> the only trauma injury that gives me the creeps is degloving

I worked with a guy who was missing most of his ring finger. I asked him about it one day at lunch. I regretted it.

Specially maxillofacial degloving. But modern surgery is amazing.

Yeah I have this about scarves ever since I read about how Isadora Duncan died.

I have a very cool ring made of tungsten carbide and carbon fiber. But I stopped wearing it precisely because of hearing stories like this.

Thats the reason I never wore any rings or necklace, or co.

You never know, when you suddenly need to move fast.

There was a scene in The Fountain where the guy ends up tattooing himself a wedding band after losing his wedding ring.

Tungsten (carbide) ring wearer here: I've looked into this and supposedly they're easy enough to crack.

Lucky for me, I bought mine for ~$30 on eBay and it's always been a bit too big for me. If my finger only swells a bit, it could probably still come off.

Easy enough to cut the finger off and reattach later. Seriously that's what they do.

I have heard claims that they are actually safer since if you take a hit, a metal ring could squeeze your finger while a WC ring will shatter instead.

It is, for all practical purposes, impossible to buy an actual tungsten ring; all sold as "tungsten" are really just tungsten carbide ceramic. Really-pure elemental tungsten is not difficult to machine, unlike common tungsten alloys.

A company near Los Angeles, American Metals, will sell you a 0.99999 pure tungsten boule for a few $thousand. You can ask for it to have a nominal (e.g.) 22 mm outer diameter, and slice it up and core out a collection of rings. The boule melt pattern on the outside is really appealing.

You can sell the rest of the rings, then, provided you can find a way to cut through the noise of the $2 tungsten-carbide hawkers. You might be tempted to paint on a design with resist and electro-plate gold where it isn't.

The scrap you cored out is pretty valuable. Maybe have the cores cut out as discs, instead of just drilling, because the "swarf" would be really hard to melt! They would resemble very heavy, thick coins; you can use a CNC machine to mill designs onto them, if you like.

>Tungsten carbide is not heavy at all. Pure tungsten is twice as dense.

Tungsten carbide: 15.63 g/cm3

Tungsten: 19.3 g/cm3

Pure tungsten is about 1.23 times more dense, not twice as much.

I am corrected.

> They have the mean tendecy to explode into super sharp pieces when you're not expecting it, so wear goggles.

This seems understated. Shouldn't you also wear armor?

A 3mm deep cut 2cm long will heal just fine on your arm with minimal first aid.

You’ll be lucky to keep an eye with the same injury even with an excellent surgeon.

Oh, that's really interesting! I guess the energy is storred in them because they underwent some plastic deformation in the press? Is that from plasticity of the WC itself or from a sintering aid such as cobalt? I would have thought pure WC would have no plasticity at all at room temperature or anything nearby.

> They have the mean tendency to explode into super sharp pieces when you're not expecting it, so wear goggles.

Will goggles really help? This sounds like it would rip your whole face..

Those things look awesome. What's cost of getting one of these?

> I struggled a lot with deciding to buy a cube. It felt wrong to spend so much money on a featureless hunk of metal.

When I bought my cube, I used it as an exercise to fight back against my frugality.

But it wasn't meant to be: it was delivered to the wrong address and I received a full refund.

Then my neighbor delivered it to me.

> Then my neighbor delivered it to me

The only thing that would make this story more perfect is if they'd said, "Wow. Heavy. What do you have in there? A cube of tungsten?"

True story: When my brother was in college, he played in the University of Illinois marching band. One year, the football team made it to the Rose Bowl. The band flew to Los Angeles to perform and do tourist stuff. On the beach, in a fit of eccentricity, he started picking up rocks from the beach and calling them seashells.

He brought the rocks back to Chicago.

Our grandfather picked him up at the airport and picking up his suitcase, said, "This is really heavy. What, do you have rocks in here?"

"Yes," my brother answered.

Good for him. There are a lot of places I've been that I was so sure I'd make it back to. Yeah, not gonna happen. But in a few of those places, I brought something back. One's mostly quartz, one's mostly basalt. With them, I can travel in time.

> But it wasn't meant to be: it was delivered to the wrong address and I received a full refund. Then my neighbor delivered it to me.

This must have caused havoc with your frugality.

The cube thwarted your attempts at frugality, so that it could spend time with you alone.

A perfect Companion Cube.

Why did you fight your frugality?

Better tungsten than bitcoins

I got one as well, around the same time actually, as a gift. I also fell into a strange fascination with it and find it fun to hold in the exact same ways as the author. Folks tend to get me 1" element (or sometimes non elemental but interesting in another way) cubes as gifts now which works out as it gives a great range of price to choose from while maintaining surprise with the guarantee I'll enjoy it.

I've had my sites set on something this size https://midwesttungsten.com/tungsten-cube/ for a while now. (about as much as I would feel safe setting down or handing to people considering the hard edges and chance of accidents) I've more than had the spending money to do it for a long time but much like the author I've just had a hard time justifying it. I suppose it's still less ridiculously than what many spend on car hobbies or whatnot. I'm sure I'll eventually get something of the nature.

I'll also add I was extremely surprised others enjoyed it as well. Of all of my desk toys/models/prints it's generated the most talk amongst friends and coworkers.

I'd like to experience a sizeable amount of iridium some day as well.

Edit: One of the most fun gifts I've received (beyond the tungsten cube) was a 1" magnesium cube. Apart from being a ridiculous fire/blinding risk capable of easily melting through the tungsten cube if set off it is even lighter than an equivalently sized aluminum cube.

> Of all of my desk toys/models/prints it's generated the most talk amongst friends and coworkers.

I'm not joking when I say one of the things I miss most about office life is decorating my desk with objects and having people react to them. Even before Delta, when things were opening back up, my office was doing "hot desks" which meant you didn't really get to personalize your space. It's understandable, but a bummer.

Do you have some kind of work chat room(s)? Just share pics or videos there. No it's not really as satisfying, but it's still fun.

For context, iridium is probably the densest material you’d want for a paperweight [1] but it’s rarer and more expensive than tungsten or platinum.

[1]: https://www.quora.com/What-is-the-heaviest-metal-I-can-legal...

To save people some time clicking through...

A 10mm cube of Iridium weighs ~21.9g. And from this source, costs $9000.

From the same source, a single gram is only $275. This means that due to the difficulty in working with this very dense metal, the cost of turning the Iridium into a cube is nearly $3000 (on top of the ~$6000 for the metal itself)!

Theodore Gray has a story about visiting a company with an electron beam furnace with Oliver Sacks to turn a pile of loose iridium beads into a bar: https://theodoregray.com/PeriodicTable/Stories/077.x3/index....

Some of the cost isn't just from using the equipment, but because you'll have some evaporation from melting in vacuum. He says at the start of the article that Sacks started with a kilogram of beads:

>After melting from both sides and a lengthy cool down period (plus a couple of "ouch, where are my gloves" moments) Sacks' iridium was consolidated into a block a little over 2" square and less than 1/2" thick, weighing 1.7 pounds. It's startlingly heavy, distinctly more so than a similar sized tungsten block (which would be about 15% lighter and about 10,000% cheaper).

If true, the melt lost 22.7% of the mass, which is pretty painful. Google is saying iridium is about $167,000 per kilo right now! I assume they've got a cold trap on the vacuum line, and recovered some of the difference in weight as fine iridium dust, but the rest is going to end up coating the inside of the vacuum chamber.

If they routinely melt platinum-group metals, I wonder how often they scrap the entire chamber to melt it down and recover the evaporate.

Normally all furnaces or vacuum chambers where precious metals may evaporate have their walls covered with some metallic foil, e.g. aluminum foil (while the worked metal is heated at very high temperatures by the electron beam, the walls remain much colder), on which the precious metals lost during heating will condense.

After a production batch, the metallic foil is replaced and the used foil is chemically processed and almost 100% of the precious metals are recovered.

Ah, that makes a lot more sense.

That story reinforces everything that I've learned about Oliver Sacks. What a cool dude.

Osmium would be heavier still (22.59 grams/cc), and a relative bargain at $1275 for the 10mm cube at the same source. Not polished/shiny though.

Osmium is the densest pure metal, but iridium has an almost identical density, i.e. 22.56 for Ir, vs. 22.59 for Os.

The difference is far too small to give you a different feeling when holding a piece of either osmium or iridium.

While osmium and iridium are the densest pure metals, there is a range of composition in the osmium-iridium alloys which has a slightly greater density than both pure osmium and pure iridium.

That happens because the atomic concentration of Os is a little higher than that of Ir while the atomic mass of Ir is a little higher than that of Os.

While increasing the proportion of Ir in an Os-Ir alloy from 0% to 100%, there is a range where the atomic concentration decreases slower than the average atomic mass increases, so the density of the alloy becomes greater than the density of pure osmium.

At higher Ir percentages, the increase in atomic volume overcomes the increase in atomic mass, so the density becomes a little lower than for pure Os.

Unlike pure osmium, an Os-Ir alloy would not be dangerous to handle. Pure osmium is slowly oxidized in air releasing the volatile and extremely dangerous osmium tetraoxide.

In nature, the normal occurrence of both Os and Ir is as nuggets made of Os-Ir alloy, usually also containing ruthenium and very small quantities of rhodium.

And, as divbzero's Quora link points out, it's going to kill you by oxidizing into a toxin when exposed to open air.

That seems to be a concern with osmium powder, ground osmium, etc. I don't think that a cube has any handling requirements more exotic than lead solder.

Less than that even. It's a noble metal and doesn't like to react under normal conditions, though hitting it with a blowtorch might ruin your day.

$9,000 for a 1cm cube. That's "winning the lotto impulse purchase" level for me.

It's not like that money disappears. Just think of it like buying gold bullion.

Unlike say, a $9000 motorcycle impulse purchase, a block of raw metal should hold it's inflation adjusted value relatively well for decades and you can sell it whenever to recoup the money.

Gold bullion has a healthy market to sell back into though.I don't know the numbers, but i wouldn't be surprised if I could easily sell gold for 80% of "market" value, whereas probably closer to 20% for something like Iridium that has a very small adressable market unless I were to expend considerable effort finding someone willing to pay what it's worth.

You could probably sell it to just about any gold dealer, as a lot of them sell iridium bars anyway. The tools they have to verify the purity of gold also work for other metals. If not, then they would certainly have connections to find someone who will buy it.

Also, you generally buy/sell on a 5-10% spread from the "spot" market price of the metal, depending on the quanitity you're dealing with. Dealers generally offer a closer price to spot when dealing with larger dollar value amounts of metal.

Iridium is commonly used in jewelry; it's one of the platinum group metals.

It doesn't have the mass awareness of gold, but it's not some weird niche material either.

Platinum might be a better fit in this "really heavy" category. 21.447 grams/cc versus gold at 19.3 grams/cc.

Metals also survive pretty much anything, including catastrophic fires.

Gold can easily melt in a house fire. A diamond ring can turn into a puddle of gold and no diamond because it burned off

Melted gold is just as valuable as gold jewelry, since they melt it down anyway when you sell it. It might be worth marginally less than an intact piece of gold bullion that can be resold without processing.

Diamonds don't have resale value anyway. They're literally a scam.

Diamonds do have significant markup depending on where it is purchased but they do still have some value. As long as the buyer can verify the certificate and the diamond is of significant quality, size, clarity, etc. it still retains value. A gemstone buyer may offer less than a private buyer (just like with cars) because they are in the business of selling the diamond later for a profit. Obviously, there is artificial inflation from the manufacturers but everyone else still has to play in the inflated market.

As for gold jewelry, this can swing both ways. An intricate piece with some sort of history attached may fetch a higher price from a buyer that is interested in that versus a scrap buyer that will just melt it down.

Similar analogies can be found with cars. A factory stock 1996 VW Golf will only be worth slightly higher than scrap value. Meanwhile, a 1996 VW Golf Harlequin will be worth $8-9k, its the same car but with a different factory paintjob. Effectively no difference in manufacturing costs since it was just made from different stock-painted panels but worth way more to a buyer simply due to the history and rarity. The cars both still have the same scrap value, a junkyard would buy both of them for the same price.

One thing I've wondered, exactly how easy would it be to find a gold puddle after a fire anyway? I mean it's not going to vaporize or walk off on its own, but is it just going to be a little solidified glob there to pick up or what?

Yes, it might flow around in the fire but it would be in the same area. A metal detector would be the fastest way to find it. Likely less time to find it solidified than looking for jewelry on a beach. Certainly less time than mining the gold.

I've found aluminum globs under fires that had cans or trashed roofing thrown in. Pretty clean, since nearly everything floats on it, and easy to spot in ashes.

Aluminum melts around 1200F. That’s a really hot fire! Was it a windy day?

(Lead, on the other hand, melts at half that.)

Once the core of the fire is mostly charcoal temperatures can climb up to 1100C. It doesn't have to be windy or even a large fire. Just need to be burning charcoal and not evaporating water or burning off volatiles.

The fires I have found aluminum globs in were long burning beach campfires and a bonfire to burn brush(big fire). The beach campfires were moderately sized but they certainly weren't bonfires built with 6-8 foot logs.

Yes but it will probably be blackened with soot which will make it hard to find.

That's my point. Gold changes shape in a fire, but it's not lost.

New form of investment?

I'll get myself a 10cm cube as a paper weight when I start and sell my multibillion asteroid mining startup.

I mean with any luck we'll find a pure iridium asteroid and bring the thing back to earth. Iridium paperweights for everyone!

Blocks of magnesium are not fire hazards are they?

Magnesium only ignites easily when in thin strips?

yeah, needs a strong heat source if it's a block. E.g. it's tricky to ignite a NeXTCube even with a blowtorch: https://simson.net/ref/1993/cubefire.html

"easily" is a relative term, it'll absolutely go up in a glorious blaze among any other actual fire but it won't set off at the slightest spark like fire starting powder or strips.

It's also a relatively pure sample, very soft, not an alloy like you'd see with magnesium casings. The block is actually a little deformed just from dropping it on the floor once.

William Osman had a video where he "experimented" with a huge tungsten cube. It's quite entertaining.

https://www.youtube.com/watch?v=9O551__3ppM

Another interesting fact about tungsten is that its density is 99.75% of that of gold. So essentially you can model how heavy something is if it was made out of pure gold with tungsten. Additionally, apparently gold counterfeiters sometimes put tungsten inside of gold bars to fake gold

Thanks for reminding me that this video exists. William never fails to make me laugh.

That is a terrible video.

I thought it was entertaining.

We use blocks like this in our electron beam welders to set the beam power, shape and focus on older machines (newer machines use a CPU/DSP controlled system). A small 25x25x50mm block sits on an adjustable height stand which is set to the height of the weld joint. You dial in the settings, hit the block with the beam and using the optics, visually check the focus and alignment. Then you move to the weld joint and start welding. For big power jobs we break out "the brick" which is 75x50x155. Its so heavy you need two hands to hold it and sometimes two people to place and line it up in the vacuum chamber.

Tungsten is the only metal you can reliably use as our machines have beam powers up to 15kW which can precisely deliver an enormous amount of heat into a pencil point sized area. Even at the common 1-3kW ranges the tungsten instantly liquefies when the beam turns on. Ive seen 1/2 thick aluminum turn into a puddle while the tungsten just gets a dent in it. You'd think copper is a good second bet but nope. Its good at heat sinking but melts way quicker.

> Tungsten is the only metal you can reliably use as our machines have beam powers up to 15kW which can precisely deliver an enormous amount of heat into a pencil point sized area. Even at the common 1-3kW ranges the tungsten instantly liquefies when the beam turns on.

I'm sorry - is there an error here? As I understand the rest of your comment, you use Tungsten because it does not liquify?

The whole block doesn't instantly liquify like other metals, just the small point the laser hit (hence the small dent after).

No error. The tungsten liquefies locally to the section of the block where the beam strikes but the surrounding tungsten stays solid. It's a poor heat conductor so it doesn't form a wide liquid puddle. With copper or aluminum the heat spreads rapidly and the pool grows wide very quickly.

What are you welding with that thing? And for research or production?

I have a collection of thin tungsten cylinders if anyone is in the market!

Glassblowers use tungsten rods to pierce borosilicate glass. When you get tungsten and a piece of glass hot, you can push the tungsten through the glass fairly easily. Tungsten doesn’t get “wet” and stick to glass at these temperatures (~2000F), unlike other metals we use such as steel or brass. We tend to buy these at the welding store (arc welders use them as electrodes or something).

Note that if you're buying welding tungsten as a plaything, avoid the oneswith the red paint on the end - they contain thorium to improve the electrical arc and as such are a bit radioactive, and shouldn't be directly handled for long periods.

I'm a hobbyist tig welder. 1-2% thoriated electrodes emit alpha particles that won't penetrate skin. It's really only a risk if you breath in a lot of the dust created by grinding the tip of the electrode to a point. That said, ceriated, lanthanated and pure tungsten electrodes are widely available.

Indeed, the thorium ones definitely shouldn’t be put into a 5000 degree flame 2 feet in front of your head. All the other metals in glass work are bad enough.

One excellent application of a block of tungsten is as a bucking bar for metal riveting. Due to its density, tungsten bars can be much smaller than steel ones, easily fitting into your hand, and fitting into tight spaces. I’ve got a number of tungsten bars and use them almost 100% over my steel bars.

Definitely. The only time I grab one of the steel bars is when it’s in a particular shape that I don’t have in Tungsten.

We put a $600 tungsten sphere on our secret wedding registry as a joke, along with lobster flavored pillow mints, etc. It arrived in the mail. My husband's high school friends had pooled their resources. Now it's on the mantle, resting amongst warm woolen pom-poms.

Some of the reviews on these are fantastic:

https://www.amazon.com/gp/customer-reviews/RZKKKAM6FE5AI

> Nietzsche once said that a man who has a why can bear almost any how. But a man who has a tungsten cube can bear any object less dense, and all this talk of why and how becomes unnecessary.

Cool cube and I want one. But a metalworking friend of mine warned against getting a ring made out of tungsten.

Apparently a climber had one on and broke his ring finger, and the EMTs couldn't get the ring off because the finger had swollen and they couldn't cut the ring due to the strength of the metal. They ended up having to amputate and re-attach the finger (much longer and it would have had to be amputated anyway, it seems).

If you are in this situation, don't cut the ring, crack it. Pure tungsten, and some alloys like tungsten-carbide, is somewhat brittle.

https://www.larsonjewelers.com/can-tungsten-rings-be-cutoff

I originally had a tungsten ring when I got married and managed to shatter both it and its replacement within a year.

Terrible for rings, just go with silver if you want or need a cheap wedding ring.

My choice was titanium, which I used to make ours. It is (IMHO) among the finest of all materials for the job.

> among the finest of all materials for the job.

Titanium should also work great for forced amputation in the case of a broken finger I suppose...

Nah, it cuts like soft stainless-steel. Garden-variety bolt-cutters will go through it like butter.

To wax poetic for a little while, Ti is lightweight, strong, warms quickly to the touch but isn't cold in winter, resists abrasion, doesn't irritate, and is almost immune to corrosion. Its strength allows a lower-profile ring without collapse, too. When making rings for our wedding, I could have used any material under the sun; titanium was our choice.

A material need not be rare to have significance, so it is with love.

What is with the anti-ring cartel on this thread?

Every metal mentioned has someone talking about losing a finger. Do you work for a silicone ring company?

It's a real hazard that is well known in the trades, but might not be appreciated by people who are attracted to the idea of an exotic metal ring but are not in situations where they will be warned about it. The warnings here seem reasonable to me.

There's an easy workaround -- if you're working in a machine shop or where getting your ring caught by something is a possibility, the ring goes in a safe place.

For me, before I touch a lathe or mill, the ring goes in my left back pocket. Every time.

Titanium is a good choice, much harder to break than tungsten and cheaper than tungsten or silver, too.

I got a tantalum ring. It look a bit like tungsten or titanium but it's much softer.

The ones I saw from a quick search were nice looking but pretty pricey. Basic Gold rings were going for the same price as some of the fancier designs so I think that would be more of a design / aesthetic choice.

Titanium / Tungsten / Silver are for people who want an inexpensive ring.

Funny because titanium is actually a very cheap material. I got a 1" cube of it for about $30. I assume almost all of the price is labor for working with it rather than the cost of the metal itself.

I mean the Tantalum rings, those are the ones going for about the same price (75-90+%) as gold rings.

Stainless steel works too

My problem with Stainless Steel is a nickle allergy. Skin gets raw, itchy and red if I wear a stainless steel ring for more than a few hours and it takes days to heal after contact ends.

I also have to test Sterling Silver as it is supposed to only be 92.5% Silver and 7.5% copper but sometimes it is adulterated with nickel and can cause me to have a breakout.

This sounds like an urban legend. "Ring cracker" tools are widely available, and can be improvised from common tools.

Scene of an emergency: hold still while I figure out how to improvise a ring cracker that can crack a solid tungsten ring without further injury to your finger.

EMTs aren't amputating your finger either. You'd go to the ER and they'd call the surgeon.

They'd also know that you can crack a tungsten ring, so they wouldn't need to do that in the first place.

If your finger is broken it will swell up so fast you may not even be able to get to the ring with something that can crack it. This is not something that I would risk for any price.

Just confirmed with my wife (ER doctor) that there is no situation where an EMT amputates your finger because they can’t get a ring off.

I don't think I ever said that an EMT would amputate your finger. I said that you might get further injuries. For instance: embedded Tungsten fragments or in case of a prolonged problem removing the ring further tissue damage.

The main point of the person you were replying to was that the finger amputation thing is an urban legend because you can shatter a tungsten ring. And the point of my reply was that an EMT won’t amputate your finger. I just assumed that your reply was refuting that point.

Ring crackers and vice grips would both work just fine.

EMTs and firefighters usually carry basic tools in their ambulances and trucks. The tools will certainly be at an ER or trauma center.

There's videos showing exactly how to do it using vice grip pliers available in any hardware store, it's very easy and takes 20 seconds.

Yes, it is. If you have vice grips handy. Emergencies tend to happen 'just like that', you don't get to prepare ahead of time unless you want to accessorize your tungsten ring with a pair of vice grips in your pocket.

There are many emergencies where innocent bystanders won't have the tools or knowledge to extricate me. I would expect ambulance and/or fire brigade services to have such tools at the ready though, just as how they have the fancy hydraulic press-metal-apart-with-extreme-force tools to get people out of car wrecks.

Vice grip pliers capable of breaking a tungsten ring is cheaper and easier to purchase than the bolt cutters needed to remove a titanium ring

I bought a tungsten wedding band and will never again. Not because of its hardness but because I dropped it on the floor and it shattered. Apparently tungsten is very brittle and is useless on a hand that does anything. Luckily it was cheap.

As others have mentioned, that band was not made of metallic tungsten, which does not shatter, but of sintered tungsten carbide ceramic, which shatters like any ceramic, even if not as easy as ceramic cookware.

I'm surprised the EMTs did not know how to remove the ring. Squeeze it with locking pliers and it will break into pieces.

Similarly, if missing pliers, you should be able to set it on a hard surface(like concrete or metal) and give it a few tough taps with something hard. They shatter shockingly easy.

Considering that in this case there's a finger inside the ring, I'm not sure if that's such an amazing idea.

Just use lighter taps :).

See: https://www.youtube.com/watch?v=yN71I3PKR6g

Haha, you're right, that doesn't look that bad

We can only pray that all EMTs read your comment such that they may be redeemed.

Out of all humanity, it seems that EMTs are at the low end of the scale for needing to be redeemed.

Exactly this. That was my first reaction when someone upthread wrote that they made a ring out of tungsten. I can only imagine that it would lead to misery at some point. You really don't want this kind of metal for Jewelry that surrounds you (wristband, ring, ankleband). You're going to get hurt sooner or later.

Ring avulsion is pretty scary too, and can happen with any metal ring.

I had to look this up: ‘Ring avulsion happens when a ring on one of your fingers is caught on an object and gets yanked off suddenly and rapidly. The force and pressure of the ring being pulled can strip off and damage finger tissues, including muscles, tendons, and bones. This is called “degloving.”‘ https://www.healthline.com/health/ring-avulsion

Ah, thanks, those are the kind of search queries that I'm somewhat apprehensive about. Especially with search engines that think it's a good idea to immediately show you images if they think you're searching for something visual.

Thankfully the article you linked doesn't contain any images.

Try finding a machinist that wears jewelry. Either they have yet to learn a painful lesson or they will have learned it directly or indirectly (colleague, machinist friend). That's one thing you learn to respect in a hurry: no jewelry near rotating machinery.

I've only spent a very small amount of time around woodworkers, but I imagine that scarves are a big no-no as well. ;)

And loose clothing, gloves, ties (I once saw a visiting salesguy almost lose his head in a demonstration lathe), in fact anything that can end up where you don't want it to.

Similar advisories hold for printing presses, farm equipment and so on. Printing presses are particularly nasty because they tend to be so spotless that you can't tell if they're rotating or not by looking at the surface.

Yeah my work mate wears a silicone band at work after almost losing a finger. I still wear my gold band but am rethinking it.

The silicone bands are pretty popular in the “outdoors” community too (hiking, rock climbing, etc.)

Tungsten is about the only minimally-hazardous substance I could find that could max out the 70-pound weight limit on a (US) Priority Mail flat-rate envelope, but that would be an expensive stunt.

Gold is also about the same density as tungsten, though it would make for an even more expensive stunt at $1.5 million.

That might be a bit over the limit as far as the insurance that they offer.

Not only that, machining that piece would take ages and wear out a fortune in tooling.

Bear in mind that we're talking about metallic tungsten here, not tungsten carbide (WC). It's a little slow and expensive but it can be machined in fairly conventional ways, using tungsten carbide tipped tooling.

Tungsten has an enormously high melting point, the normal way tungsten parts are produced, for typical industrial purposes such as radiation shielding, is sintering (powder + heat + pressure) to near-net-shape, finished with a machining pass.

Good point, that is a huge difference in hardness.

Below I suggested it would be easy for EDM or ECM. Have I been misled?

EDM will take a very long time, you are going to take off a few microns per hit, and ECM will likely take either an insane amount of power or will take forever across such a large surface.

Compared to say machining aluminum or steel you will be practicing some patience.

Not necessarily a bad thing to have in the world of metal working. ("increased feed speed is not a substitute for bad planning")

I guess I was thinking that ECM would take less power per mass on tungsten than on things like steel or copper, just because each atom is so much bigger. I'm not very clear on the chemistry, but suppose that we're electrolytically oxidizing each tungsten atom into an orthotungstate ion by withdrawing two electrons from it, with an electrolyte of something like chloric acid or sodium hypochlorite so we don't have to pay more electrons to free up some oxygens. Then at 100% Faraday efficiency we'd cut away 184 daltons of tungsten for every two electrons; contrast with iron where you still need to withdraw two electrons to get a stable water-soluble ferrous ion, but that only buys you 56 daltons of metal removal. Even copper, where the cuprous ion only costs one electron, you only dissolve 64 daltons.

There's also the issue of electrode potentials: sucking a coulomb off your anode at 0.5 volts takes only half a joule, but sucking off the same coulomb at 2 volts takes 2 joules. I don't understand standard electrode potentials well enough to predict what voltage you need for efficient tungsten ECM, but on first glance at the reference table, it doesn't look particularly bleak. The tungsten entries are in the middle of the table, near things like lead, tin, and iron, rather than way down on the upper east side with hoity-toity mercury and iridium, much less out in the ethereal districts where gold and ozone dwell.

Per unit of mass yes, but there is rather a lot of mass for a given volume. And those are relatively slow processes when it comes to dealing with surfaces. Perpendicular cuts should be a lot quicker (you only have to separate the two sides, in theory one slice of atoms would be enough but in practice you'll end up with some minimal cutting radius).

Fascinating processes by the way, and the precision that you can reach with EDM is insane.

Hmm, I thought ECM and tap-disintegrating EDM (which is not very precise and does use a huge amount of power, unlike, say, wire EDM) had pretty astonishingly huge MRRs?

I think the density ratio for tungsten and steel (19:8, just over 2:1) is actually more even than the atomic mass ratio (23:7, just over 3:1). So I'd think that even on a volume-per-coulomb basis ECM would cut tungsten faster, assuming comparable faradaic efficiencies. Do you have any idea about the electrode-potential question? I'm totally lost.

No, but if I had a machine like that here I'd definitely give that a work out because this is an interesting question that I normally would not have considered.

That's a question worth settling, from memory the speed is not so much a function of the material as it is of the current density that you can achieve with the gear you have. Thousands of Amps will get you some pretty good speeds, on the order of a cubic cm of material removed per minute for a 25KW machine.

I also wonder what would happen if you tried to plasma cut it, that should work as well.

If there is one thing I really miss from life in Canada then it was the fully equipped machine shop, that was such a great thing to have. You could go from idea to a pretty decent physical implementation fast than you could have ever mail ordered the parts and there is so much satisfaction in working metal. The plasma torch I had there was a relatively small one (12 KW) but it still cut anything an everything I ever threw at it with pretty impressive speed. But I never tried it on Tungsten. Missed chance! I suspect it wouldn't work all that well because Tungsten isn't the best conductor and probably would backsplatter all over the place from the compressed air dispersing the metal that would melt rather than evaporate so you get a puddle rather than a stream of gas.

I don't really understand what the limiting factors on ECM speed are. There's electrolyte heating, cathode heating, bulk electrolyte resistance, formation of salt boundary layers on both the cathode and the anode, and so on. But one thing I do know is that MRR is proportional to the area of the interelectrode process gap: twice the area gives you twice the MRR at the same current density, whether the current density bottleneck is in the cathode, the anode, or the bulk electrolyte between them.

Electrolytic processes are really interesting and complicated, and 200+ years after Davy used them to revolutionize chemistry, I think they're still underused. I'm preetty sure you can produce Fresnel reflectors for a given wavelength, for example, by anodizing aluminum foil to about a quarter-wavelength depth, and across a wide range of visible wavelengths by anodizing it to about 3 microns depth, with the electropolishing effect inherently eliminating the small asperities that make it so slow to produce lenses and mirrors by grinding.

Plasma cutting should work, but should be slower on W than on iron; WP says that at room temperature its specific heat is 24.27 J/mol/K, but at 183.84 g/mol, that's only 0.13 J/g/K. For iron the same figures are 25.10 J/mol/K and 55.845 g/mol, so 0.45 J/g/K. So tungsten should heat up three times as fast with the same power output at room temperature; but tungsten's heat of fusion is four times higher, and I think that's actually the dominant component of plasma-cutting energy consumption. But I think you have roughly four orders of magnitude more knowledge about plasma cutting than I do.

That Fresnel reflector idea sounds super interesting.

Has anybody tried that?

Not that I've heard of; it's possible that someone tried it and it doesn't work for some reason that isn't obvious to me, and then they didn't publish their negative result. I published the idea in 02019 in https://dercuano.github.io/notes/mechano-optical-vector-disp..., but I haven't actually tried it, and not many people read Dercuano, in part because most of it is ideas I thought up but haven't tried.

Reading I've done since then explains that, when anodizing, the anodized layer grows up out of the surface roughly as far as the surface gets depressed, and the anodized layer has a higher refractive index than air, so, for many purposes, you don't need to etch nearly as much metal. (The anodized layer is thin enough that it would be adequate in many applications that normally require a first-surface mirror, though not all.)

It's well known that if you're instead anodizing silicon you can fabricate a rugate filter by varying the anodizing current to vary the density of the anodized layer, that when anodizing titanium you get brilliant iridescence due to the high refractive index of the oxide and consequent strong single-layer dichroic filtering effect, and that there's a negative feedback on the current from the oxide layer thickness in all of these cases, requiring higher voltage to get a thicker oxide; this should also tend to even out small surface asperities, and is not the same effect as anodic leveling. The possibility of including such dichroic filters on the surface of the holographic reflective optics, with wavelength response tailored at a submillimeter or even submicron X-Y resolution, could be interesting for fabricating a wide variety of optical systems.

If you end up trying it, I'd love to hear about the results! If I'm not dead by then. Though I'm sure you have a long list of ideas of your own that you can't wait to try, like everyone else capable of trying this sort of thing.

All this seems to me like a crucial enabling technology for feedback control of machine tools, because light waves don't distort or change their dimensions much when the temperature in the room changes or there's a side load on your gantry.

I need another life ;) Seriously though, this is worth pursuing. But I've more or less decided to dedicate the rest of my life to music and to start this all up again would require a small fortune and a very large dedication in time. Still. Tempting.

Oh, I had no idea! I thought you were doing some VC-fund thing.

EDM can cheese-wire right through blocks of tungsten.

That I readily believe, but to face a sheet is a different matter, which I believe was the application the OP intended.

You can also cut tungsten with water jets loaded with abrasives, I've seen a 2" thick block cut like that, it was quite impressive. But that won't get you a surface. You'd need to start with a sheet of the right thickness.

True. I bet a quick call to Rembar would put you on your way to a source if you just need sheet.

Tungsten foil/sheet isn't that hard to come by.

I've only ever used bar stock, but I imagine the same suppliers would have sheet as well though I can see a couple of arched eyebrows when you order that, plus a question or two if you are absolutely sure they have your order down accurately.

Cost a small fortune too.

Thank you very much!

Rembar and Plansee are consistently good.

Cut it off the end of a bar.

Hehe. Very funny :)

I had a neighbor a few years back who was a retired mechanical eng & machinist and as a retirement gift someone gave him a calibrated high percision gauge block set. There was some weird brain tingle I would get handling them, I think simply due to the extreme percision of them, I wonder if the sensation from handling the cube is similar?

> gauge block

It's so cool how they wring without magnetism.

https://www.youtube.com/watch?v=Z5XOk1oMFh0

There's only one way to find out...

This reminds me of the infamous cube of saguaro rib wood from Dwarf Fortress

[USE_MATERIAL_TEMPLATE:WOOD:WOOD_TEMPLATE] [STATE_NAME:ALL_SOLID:saguaro rib wood] [STATE_ADJ:ALL_SOLID:saguaro rib] [PREFIX:NONE] Density was determined experimentally. Contact Uristocrat for a sample if you want to verify this yourself. A 6g (+/- 0.1g) piece of dry Saguaro wood had a volume of approximately 14 cm^3 (+/- 1 cm^3) [SOLID_DENSITY:430] [STATE_COLOR:ALL_SOLID:ECRU]

Source: the 'raws' link on the page http://dwarffortresswiki.org/index.php/DF2014:Saguaro

You can get cubes of most of the solids in the periodic table here.[1] Some are very expensive, but available.

[1] https://luciteria.com/metal-cubes

What's not 100% clear to me, after reading through some descriptions, is which metal cubes I could handle semi-regularly without damaging them (iron? will it rust?) or endangering myself (lead? how likely is handling it to poison me?).

It seems to me that the point of buying a cube of some metal is to feel its weight and texture, to see it respond to light. If you're just going to keep it in a capsule and never take it out, you could just have a photo or video of the metal.

What elements can you hold in your hand without either you or the element taking damage?

In case you haven't seen it, https://englishatlc.files.wordpress.com/2016/03/randall-munr...

I have a few of the non toxic ones. I like titanium most since it has a decent weight and doesn't make my hands smell like copper.

Some of them will oxidize and if you want to stop that you can coat them in a clear resin. I wouldn't touch lead even with the resin coating as I wouldn't trust it to not chip off.

I can hardly see lead chipping, it's much too soft for that. In general handling lead in its solid state is pretty safe. It's mostly lead dust you'd need to worry about. In any case washing your hands after handling lead is pretty much a foolproof way to be safe. It doesn't absorb through the skin.

You wouldn’t want to be handling it like a desk toy..

Probably not no, but as a display item it's absolutely fine. You're not gonna ingest lead from just touching a cube of lead every now and then.

They even have uranium cubes! Depleted uranium though, so it's no good for your garage nuclear weapons lab.

https://luciteria.com/metal-cubes/uranium-cube

My dad owns both a tungsten cube and a tungsten sphere. I slightly prefer the sphere, the smoothness and lack of corners, combined with density, makes it really try to slip out of hour hand.

Can be a bit dangerous for your floors, but lots of fun to hold.

I have a 2" cube and wish I had the sphere instead for sure

I bought a cube of aerogel and feel the same way about it, with the obvious distinction of it being insanely light not heavy.

I have a cube of aluminum the same size as my 1kg cube of tungsten. It's weird feeling the insane difference between two solid blocks of metal.

I bought a set of 1cm element cubes awhile ago. There is definitely a change of perspective of density when you see several things of one generic size, and yet they are dramatically different weights.

I think it's fairly common to see volume and assume weight. And less volume is often assumed to be a structure issue, like expanded metal vs solid blocks of metal.

I held a neptunium (20.45 g/cc) sphere once. It was about the size of a baseball and I hard the hardest time lifting it. It was like lifting a full gallon jug of milk when you think it's empty - you apply a force and it doesn't budge. I had to lift it as if I was lifting a stack of books to get it off the pedestal.

Uranium is the heaviest naturally occurring on earth, so after that on the periodic table (uranium, neptunium, plutonium…) things are made with collisions in the lab.

I bet a lot of energy went into creating that sphere…

osmium is denser than uranium, the issue is that it's quite expensive.

I'm quite curious what the circumstances of that would have been. I looked it up because I thought I was mistaken, but ya: it's nuclear reactor byproduct and itself capaple of being turned into a nuclear weapon (or only some isotopes maybe? Not sure). It also apparently is capable of just starting on fire in open air, is poisonous, radioactive obviously and accumulates in the bones. Sounds like fun stuff.

Was it warm? That was a rare experience; not many people will have done so.

I have a tungsten wedding ring and the weirdest thing about it is how it bounces (on the occasions when it’s flown out of my hand - I don’t make a habit of doing so normally).

It’s dense/heavy so seeing it bounce so well is somewhat paradoxical.

(Side note: it may be impossible to cut through in case of an emergency but your finger is not.)

I believe you can shatter then with vice grips in an emergency.

> may be impossible to cut through in case of an emergency but your finger is not

Was seriously considering tungsten recently, but ended up going with titanium for this exact reason.

I purchased a 35 pound tungsten racing weight about 15 years ago, 70% tungsten if I recall. It's large enough that it's triggered my "why do I have this?" sense, but it is still cool to hold.

It's very important to realize that it's not a safe object, the kind you might leave on your desk at work.

If someone tries to pick it up for some reason, it's quite likely that they'll drop it.

Gotta say I love the ad copy for the 10 pound cube:

    ADD to your collection! This cube is the larger version of the world famous tungsten cube
    COMPARE the density to our 2.5" Aluminum cube to enhance the experience

How about the 4" 40 pound $2,999 one?

> WHY? We thought nobody would buy our 17.6lb, 3" tungsten cube. We were so, so wrong

My sister owns two shoe stores in LA.

It wasen't till she raised her prices significantly things got going.

Wealthy measure value by price. (I don't get it.)

Shoes (especially the ones people buy for fashion value – think Louboutin stilettos vs. something more functional like New Balance sneakers) are a Veblen good. Their perceived value increases with their price. Like art.

https://en.wikipedia.org/wiki/Veblen_good

Also, if a market is efficient, prices will closely track (marginal) use value. If a brand can demand a price premium, it's because their products are higher quality, and nobody has been able to produce a comparable product at a lower cost. Red Wing boots are more expensive than Timberland boots, for example, because they're made from full-grain leather and have good quality control, and they will last the rest of your life if you care for them properly. (They're more expensive than New Balance sneakers, too, but Nike sneakers are the same price as Red Wing boots without being of high quality, for the Veblen-good reasons you cite.)

That's why when I buy wine for my girlfriend I don't buy the cheapest brand. It's not that I think the wine market is efficient, particularly when I'm at a supermarket that can charge whatever price they want instead of comparing prices at https://1000corks.com/; it's that I think my ignorance of wine is deeper than the market's inefficiency.

I'm getting crazy deja vu, I swear I've read this exact thread before.

edit: I have https://news.ycombinator.com/item?id=27522826

That is not quite it - in a relatively efficient market with numerous transactions, price can be a good indicator of value. Basically: "This store is busy selling lots of shoes, and apparently a bunch of people are buying them, so they must be worth the price."

I do this sometimes with cheaper stuff that I don't know much about. E.g. A shovel or something. I don't know much about shovels, but I know I want a good one. So I will be biased toward the more expensive shovel on the rack, assuming I can afford it. If it wasn't better, then presumably all the people that really know about shovels wouldn't buy it, so then it wouldn't be for sale.

Anyway, the logic here isn't perfect obviously, but still makes reasonable sense and works out okay for stuff you can easily afford and don't know much about.

Thorstein Veblen wrote a whole book about this phenomenon. Tl;dr: https://en.wikipedia.org/wiki/Veblen_good

Once it gets large enough, it will end up at MOMA.

Imagine how much a really big cube of tungsten would weigh. Installing it at MOMA would itself be the art.

Presumably in one of the basement spaces.

I wonder if anyone is manufacturing tungsten dumbbells. Would be very pricy, but also super cool.

'Official' sports kettlebells are all the same physical size but are available in a wide range of weights. For sizes 8kg to about 32kg they just use steel. For heavier ones they use lead. The very heaviest kettlebells contain tunsten.

The brittleness would be an issue. Shattering when you drop it isn't really a property you want in dumbbells.

This is why I prefer uranium dumbbells

this is the sort of value driven advertising that I appreciate

At Christmas my partner’s family always struggle to know what to get me. One year I just said anything made of titanium. Everyone thought that was super weird.

Now I’m thinking it must have been the metal’s low density.

I hope I'm not too late to the cube measuring party. My friend gave me the 4 inch one for my birthday, and it's been a source of constant amazement ever since: https://midwesttungsten.com/tungsten-cube/?sku=40400-03914B&...

It weighs over 40 lbs and it's almost impossible to lift with one hand.

I haven't smashed anything with it yet

Generous friend at $3K!

He's a TechLead at a FAANG company

Still around 1% of his annual take home!

I often marvel at the densities of the various heavy metals especially compared to steel. The densest of them like osmium are almost 3x as dense!

I wish I could afford an osmium cube. I guess tungsten is the best cheapest-yet-still-heavy option.

Tungesten is only 10% less dense than osmium. I doubt you could tell the difference without a scale.

Osmium spontaneously oxidizes to a gas that is deadly poison. A sphere would be safe kept in oil. Do not be around when it is being polished.

Osmium is not good for you.

If tungsten isn't dense-enough for you, consider platinum or rhenium.

1kg of rhenium costs $265 while 1kg of platinum costs $30K.

I'm not saying one is a better choice than the other, but I know which one I'd get.

Where are you finding rhenium for $265 a kilo? Lowest I found in a few minutes of googling is $1540.20: https://www.amazon.com/Rhenium-Metal-99-8-Pure/dp/B08FCX61QD...

(Description says it's "great for melting". Good luck with that!)

When this was posted in 2019 it compelled me to get a tungsten cube as well.

One additional benefit that gives me more joy than fidgeting with it: it is great educational prop. Kids that visit my place have a habit of picking it up, either by their own initiative or prompted by me. Being surprised at the weight they start asking question and are then receptive to hear me give a short explanation. I love that curiosity.

Somewhat-tangentially related: I’ve always found the concept of [Rods from God](https://en.wikipedia.org/wiki/Kinetic_bombardment) (kinetic bombardment of tungsten rods dropped from orbit) fascinating.

I've been dreaming about getting the 4" tungsten cube for a while but could never justify buying it. I would need some extra truly disposable income, like as a side effect if I got really lucky gambling a marginal amount. Sadly in the last year it's price has jumped up 50% from $2000 to $3000.

Much cheaper if you can negotiate a price while cutting out the middleman (Scamazon):

https://www.tungstenheavypowder.com/tungsten-balls-spheres-c...

That place looks like you're meant to shop in bulk. Having one cube would be cool, but I probably don't need a thousand of them.

The prices are listed as "Request quote". So it could as well be more expensive

Kids ask "ahh, gee, when will I ever need to use geometry?" and the answer is when you realize you got ripped off by paying the same price for a 1.5" diameter tungsten sphere as you would for a 1.5" tungsten cube.

In terms of bullion value, absolutely. In terms of cost to manufacture, maybe not? I can't imagine making a sphere meeting any kind of surface tolerance is any easier than making a plain old cube to a similar surface tolerance.

I also have this cube as part of a set. As a far as desk accessories and toys go it's unique and a fun thing to show off.

If you get the set that has the copper cube beware that the copper one will oxidize and discolor if you touch it a lot.

Bar keeper’s friend will shine it back up nicely!

I wish someone made a standard 608 (fidget spinner, skateboard, etc.) deep-groove ball bearing entirely out of Tungsten - it would be the ultimate desk trinket and I bet it would have the longest and most satisfying spins.

The tops look like fun: https://midwesttungsten.com/tungsten-shapes-toys/spinning-to...

LOL at the Pinewood Derby tungsten blocks. Feels like cheating no?

No, there is a weight limit. There is no practical size advantage compared to using cheaper lead weights.

I suspect it does allow for design and distribution flexibility. I bought some of that sort of weight (and some tungsten-infused putty) for trying to add additional weight to improve the pulling power of a model locomotive. The putty's malleability and small size made it more amenable to fitting in the cast body.

Ideally with Pinewood Derby cars, you want to place the weight up as high as possible (in the rear) to convert potential energy into kenetic energy.

Tungsten weights are smaller, so the center of gravity can be slightly higher if you elevate the weights.

The product page says "Simply position the weights on your pinewood derby car and super glue them in place."

So if you're just glueing them to a standard model without elevating the tungsten weights somehow, they would actually be less effective than a less dense material, because the center of gravity would be lower.

If you did elevate the tungsten weights, whatever height that would match the top height with standard weights, the extra amount of energy would most likely be negligeable, and possibly lost due to variations in the track. Over a hundred races it would probably come out ahead slightly more ahead, but Pinewood Derby races are single elimination.

If one was sparing zero expense, using wind modeling software, etc for their Pinewood Derby, then yes, tungsten weights would be the way to go.

(I need to learn how to use wind modeling software now.)

Foreverspin make spinning tops out of all kinds of interesting materials including tungsten.

Pro tip: as with many things on Amazon, you can usually get these cubes (or spheres) for a fair amount less on eBay.

I have plenty of samples of explosion bonded metals that I fidget with in a similar manner. Samples that combine metals with different densities feel unnatural in the hand.

My wedding ring is tungsten; my wife and I decided to go with, shall we say, non-standard metals for our wedding bands to keep the costs down. I got her the usual gold/diamond sort of ring for engagement. We figured we could always get platinum or gold rings later.

I've found that I really love it, and now we may not replace mine at all. It's hilariously heavy and has a nice brushed finish.

Good luck cutting it off in an emergency.

You can easily shatter it with a vice grip or locking wrench, and with the rise of tungsten wedding bands EMTs and hospitals are more and more equipped for this.

The better way to deal with that problem is by not having it in the first place.

Don't cut, shatter. Grab some channel locks and be free.

Vice grips would probably be your best bet because they allow you to adjust the diameter they grip at fairly precisely hopefully avoiding further injury to your finger (such as: embedded tungsten fragments).

I use channellocks, the width setting feature accomplishes the same goal, using vice grips takes too long. But do you, I suppose.

I didn't realize that tungsten was as heavy as gold. I always wanted to to hold a gold bar for the same reasons. When I see a picture of someone holding a gold bar, I always wonder if they are struggling much more than apparent because of the insane density (almost 20x that of same volume of water, 3x that of steel). I can't afford the $600K for a gold bar however.

Bank of England museum had a holdable gold bar. And yes, cage around it was probably for prevention of body damage, rather than theft.

Then you'd find this interesting too: there's quite a lot of gold stolen or faked like this:

"Exclusive: Fake-branded bars slip dirty gold into world markets"

https://www.reuters.com/article/us-gold-swiss-fakes-exclusiv...

Damn. Midwest Tungsten Service now owes 'defaulty' a nice little Thank You card.

If anyone wants to compare, my order ID is 10000107xx ;)

I clicked on this post out of standard curiosity.

Now I have a tracking number for a cube of tungsten that will arrive at my office by tomorrow afternoon.

Happens.

1” copper sphere. Satisfyingly heavy and wasn’t expensive, maybe $15 at the Smithsonian gift shop.

I keep it next to a similarly sized, nearly spherical light gray pumice stone I picked up near Crater Lake years ago. Satisfyingly light!

I was given a tungsten carbide ring that’s supposed to be easy on the skin, but it rotted my flesh. I tried not to read anything into it.

I have a 2kg tunsgsten sphere. Also deeply viscerally satisfying to hold, and makes a great party trick.

I got the big one from Midwest Tungston, about $700. Well worth it.

I love letting people hold it. I call it my heavy ball.

I wonder if you could mill a dumbbell out of it, so even the handle itself is made of Tungsten. You would have a fairly normal looking 10Lb dumbbell that weight more than 10Kg or 26Lb. Everyone coming in the house would always (somehow) pick up these Dumbbell.......

I can see some practical joke potential here.

This is one of those moments I feel so out of touch with the community here. Is this even real life?

Maybe you'll prefer one of the million articles about a passive £10k MRR, or how I sold my Twitter bit for an infinity billion dollar valuation, but this thread is about someone who spent a slightly disconcerting amount of money on an entirely inert, but hefty, cube of material and finds it pleasant.

I actually had the opposite reaction. A few months ago, I was researching a project involving a counterweight, and the periodic table led me to tungsten on account of its density. That was until I saw the price.

Ever since then I have been vaguely considering buying a tungsten cube as a curiosity. I am bemused to find that others on hacker news seem to have arrived at the same idea.

Totally by coincidence, yesterday I was trying to plot out the cost/kg vs. density Pareto optimality curve. Construction sand is US$0.03/kg and 2.4 g/cc; magnetite is US$0.10/kg and about 5 g/cc (I don't have the notes in front of me); scrap steel is US$0.20/kg and 7.9 g/cc; scrap lead is US$0.95/kg and 11.3 g/cc or maybe a bit less; tungsten is US$30/kg and 19 g/cc; and osmium is US$13000/kg and 22.65 g/cc. I'm interested to know what I'm missing; is there anything denser than steel but cheaper than lead, for example, or denser than magnetite but cheaper than scrap steel? Is there tungsten carbide that's cheaper than tungsten?

Mercury is denser than lead but doesn't have a well-defined market price any more and has certain disadvantages. Many mercury amalgams would be a better substitute in many circumstances, but they might impose high costs on you for reasons that come down to pure superstition.

Aha, yes. I wanted one for a mini periodic table.

Would you include radioactive elements in your real life periodic table?

No, because they would change into other elements :)

If you take a closer look, it's a brilliant sales pitch with an affiliate link to Amazon.

I see two links there, neither is of an affiliate type.

I have a block of tungsten about the size of my fist. Got it at a missile test range. When the explosives are replaced by the telemetry unit, empty space is packed with tungsten to make up the weight difference. The target area was filthy with tungsten blocks.

I visited a national laboratory for an experiment and saw the tungsten bricks the size of a normal building red brick) they used to shield parts of experiments from high energy particles. They weighed about 60 lbs each.

i bought a CNC so I could make my own cubes. It's very nice. I often make objects just so I can hold them later.

Wait.... are you being sarcastic?

Or did you really spend $5,000 on a machine for your hobby of making cubes just so you can hold them?

If you are serious, I think we could be friends. Maybe I should make a subreddit for people like us?

I spent $2K (X-carve). I've made spheres, cubes, boxes, various 3D shapes I bought on Ebay, and keep the parts around (they're nice to look at as well as hold during long meetings). A cube with filleted edges is particularly nice, although you can make that easily with just a table saw and a sander. If you sand it enough, it can be unbelievably smooth. or you can make it rough.

note that I'm mainly doing wood because the x-carve can't carve aluminum easily (no idea about tungsten). If I could make metal cubes, I would.

The actual hobby here is all sorts of wood projects, like tables, arts, etc, but I still make small geometry pieces all the time because I enjoy 3D graphical objects in the real world.

I mainly read https://www.reddit.com/r/CNC/ but you may also find this interesting: https://www.instructables.com/Turners-Cube-Manual-Machine/

Love the Turners Cube, can that be done with wood?

If you drop it, your floor won't like it. My 2lb one is great though!

around the time of elementary school i had a ~15cm diameter steel (or may be something harder given where it came from - i didn't pay attention what it was made of, it was just pretty heavy) ball from a ball bearing from a driveshaft of a Navy ship. While not tungsten, it was still pretty great toy. We even played soccer using it - the style is very different as just strongly hitting it with or trying to abruptly stop with a foot would only cause pain to the foot, and the ball also would naturally not fly far :)

"The Simpsons Did It" https://www.youtube.com/watch?v=VTLYris4kJU

Love this. I bought a 3" mostly-tungsten cube a few months ago.

Almost without fail, every time I walk by it I pick it up.

And without fail, every time is satisfying.

(The 3" cube weighs ~18 pounds.)

I instead bought a lamp with tungsten filament filled with Xenon gas for $5. Sometimes I slowly apply a little current to it to see the filament radiate. This is a 150W halogen bulb. I don't know what the crystal is made of, but tungsten and xenon are interesting.

I really want to get a gold plated one. The density of tungsten is less than 1% different from gold

Apply some affordable gold leaf on it after thorough solvent cleaning, and rub it in so it bonds with the surface.

I want to buy one but looking at the Amazon Canada listing, it's gonna rack up to $250 + tax

Same in Germany, it's 250 EUR

~ 180 EUR if you order directly from https://midwesttungsten.com. Not sure if it's covers the import tax or not though.

In Germany, you can get your tungsten at Smart Elements

Way more expensive - 120 eur for 1 cm3 cube.

https://www.smart-elements.com/shop/tungsten-precision-densi...

If you are willing to sacrifice a little on the appearance they have 1kg tungsten "ingots" for 99€.

https://www.smart-elements.com/shop/tungsten-electrode-99-95...

I love this kind of thing. My favorite fidgeting things are two 2-inch stainless steel ball bearings I got from Ebay. Perfectly round to the eye and mirror smooth. I sit and clack them together; the sound and sensation they make is addictive to me.

I kind of got the gold bug after the 2008-9 crash and bought a few gold coins. Even holding just an ounce of gold, you notice how much more substantial it is than say, a "silver" dollar, which is the same size but weighs a fraction as much.

I've got a couple similarly-sized hunks of aluminum and vanadium that I got from a steel mill tour when in college. I enjoy the difference in densities in my hand, but I don't know about $130 of enjoyment for one more in the set.

This reads like they're allegorically throwing shade. At what I'm not sure.

I wonder why it is 5% nickel/iron -- availability? Machining purposes?

Because of tungsten has the highest melting point of all metals, it very expensive to cast pure tungsten ingots. Instead, powdered tungsten is mixed with small amounts of powdered nickel or other metals, and sintered.

Also pure tungsten is often excessively brittle.

The Amazon seller mentions that pure tungsten is typically too brittle to machine.

Machining

I have a tungsten cube and some tungsten dice. They're impressive to hold, and make a nice satisfying thunk when the dice are thrown.

I also have a magnesium cube. Really amazing to compare the weights.

Dammit, I'm gonna end up buying one of these, aren't I?

I too have owned a tungsten rod for the same reasons. it's very nearly exactly the same density as gold, but cheaper.

I was expecting to read "I love my precious tungsten cube... my precious" in the conclussion

Tungsten beads are also popular as a weight for fly fishing nymphs due to their density.

Hmmm, now there goes my compulsive spending over the weekend, yeah i'll get one

This reminds me of Bill Gates who owns a small amount of every chemical element.

I had to look this up. It seems he has a periodic table with lots of little cubbyholes with pictures and items representing the element, but not every element is actually there.

It's hard to find a good source for details about this display, but he has cubbyholes for all of the lanthanides and actinides, so there must be some that don't have the actual element being represented.

Yeah, I imagine that it'd be hard to get ahold of some technetium or astatine

Francium is the one I always think about. My understanding is the only source is as a decay product (probably from uranium) and that there's somewhere on the order of one ounce of it in the entire planet at any given time.

Not only that, but it's only true francium if it comes from France.

I love my tungsten cube <3

The Amazon reviews make it seem like this is a meme product.

I'm sure someone is legitimately buying eg the 55 gallon drum of lube.

...that said, had I organically encountered the tungsten cube on Amazon, I absolutely would google around to make sure it was, like, real.

Large animal veterinarians, condom manufacturers, sex shops.

Sure. The point is that despite the obvious legitimacy of the listing, all the reviews are memes.

This is cool, but I still want to stack some gold coins.

…that’s a sphere though

It's so dense that over time, the corners are pulled to the center by gravity.

(the picture is a separate 3kg sphere he bought after the cube)

The more accurate title would be "My 95% Tungsten 5% Nickel/Iron Cube"

Calling it a tungsten cube is incredibly accurate. Not very precise though.

If you're gonna be pedantic then try to do a good job of it.

Tungsten rocks.

I work sometimes in a metal shop where Tungsten alloys abound. This might be the stupidest hn post I've ever read.

You bought a piece of metal at vastly inflated prices for a very narrow range of performance over a specific set of conditions. Nothing more. Being the hardest isn't being the best. Tungsten is extraordinarily brittle. A hard drop on concrete could crack it.

I'd also argue without a MA (metal analysis or labsheet) you probably bought some tungsten. Lead, slag, tin and other undesirable byproducts also weigh a lot. Your cube, without proper inspection, may also be slightly radioactive as its likely sourced from scrap. This could be good or bad, but the cube most definitely isn't a meaningful purchase.

Every material more dense than tungsten costs more than tungsten, and the same goes for anything that even close close. Only thing you need to do to determine if you were screwed or not is measure the density. Since it's a cube the only thing you need is a ruler and a scale.

As for the value to a consumer. That comes almost entirely from its density not its hardness, something you'd know if you read OP.

As for the "vastly inflated prices" if you have the ability to produce and sell 1 kilogram cubes with the side length of an inch and a half for significantly less than OP paid then you should consider selling that information and retiring.

What are the materials with similar, but lower, densities? WC, I guess, at 15.63 g/cc; what else?

Apparently wholesale tungsten costs US$30/kg, which is about one fourth the US$130 cost the guy paid. I'd think either wire EDM or wire ECM would be able to dice tungsten into featureless cubes for a lot less than US$100/kg. Its brittleness wouldn't be a problem.

Also, it could very easily be impure, or even not tungsten at all; lots of people have gotten tricked into buying tungsten-carbide jewelry they thought was tungsten, and tungsten carbide isn't even metal. The Amazon seller says it's actually 5% nickel and iron, though I'm not clear whether it's an alloy or a powder-metallurgy sinter using those metals as sintering aids. Alloys aren't necessarily less dense than their densest pure component, so impurities might not even lower the density. X-ray fluorescence would be a cheap way to detect heavy-metal impurities (though not, say, boron, carbon, or nitrogen).

The guy is excited about how it's durable and will last for a long time. I think he will be disappointed if it really is so brittle that he chips the corner off by dropping it on the floor. Probably the nickel and iron will prevent that.

> This might be the stupidest hn post I've ever read.

I don't know... Seems your own post has missed the mark pretty sharply as well.

To me, it was abundantly clear that the purpose of this tungsten cube is not for engineering or practical utility.

Yes, but it seems like the Pet Rock for this crowd. It's entertaining to give it a heft, but I doubt if it will see as much daily use as his amortization projection suggests.

I think a better desk objet is a Curta calculator.

> he purpose of this tungsten cube is not for engineering or practical utility.

I would think you can easily sell it for the same or better price. It's like gold. It's a capacitor of wealth

If it brings OP joy, it's a reasonable and meaningful purchase