Here's a rabbit hole if this sounds like fun to you - https://natrontheory.com/index.html
The focus and color in those graphics makes them look like AI-generated graphics to me.
Normally you purify the quartz first, but here we're discussing what molten washing soda would or wouldn't do to granite. The quartz in granite normally forms a continuous phase, so as long as the quartz remains solid, the granite will remain solid.
Granite melts at a lower temperature than pure quartz, and I'm not entirely sure it wouldn't just melt before the washing soda had an effect.
Current methods of cutting pretty much anything including stone are absurdly more precise than what Incas and Egyptians had. We can cut stuff like diamond lenses down to 10-100nm roughness.
We also don't build carriages as well or have an army of craftsman doing it, but it's lost/regressed because there's no economic incentives.
There are a few that know how to do it by hand, but mass production has evolved.
https://youtu.be/uR-hY7hUsaY?t=79
I have nothing but respect for the skill and professionalism of the ancients, but I find it extremely distasteful when someone tries to express this by putting down their modern counterparts.
It's the ability to precisely measure and mark huge pieces of rock what looks like a miracle to me. Producing the exact shape is easy when you can always check how close to the desired shape you are, and it's the hard part.
I think the question is also really hard to answer in a non-answerable way because if you don't know you've forgotten who do something you simply just don't know. If you sub-divide humanity in to factions certain factions have lost the economic ability of doing some things for example have been lost to America. While humanity can still do it certain places would be totally lost without the existing tribal knowledge. It would take us a long time to reinvigorate a tool and die industry in America its not a lost thing but if you can't do it commercial currently can you do it at all?
Hopefully that's nota weird direction to take the discussion in
For example, Roman concrete, that strengthens in sea water: https://news.mit.edu/2023/roman-concrete-durability-lime-cas...
No technology was really lost, we just can't agree on how they stacked the stones into pyramids. The stonecutting technology they used is very well understood and we even have real actual tools used by the actual ancient Egyptian stonecutters and some of the tools used to manipulate and place stones.
There's also several incredibly solid theories on pyramid construction, but to verify them would require investigating the actual pyramids, which Hawass will not allow.
https://www.youtube.com/watch?v=mysYT260dqU&list=PLuROoe7EZ3...
We are pretty good at cutting stone, but not very good at cutting stone with the resources available to the ancient egyptians. So in some sense the technology has been lost: but that's more because there aren't really people try to perfect that craft, as opposed to because of some magical trick or technique that we don't know anything about (Though it's murky exactly what approaches they used, that's because there's multiple plausible ones and it's hard to pin them down, not because there's no plausible ones we can think of).
I also think that some parts are really weakly-reasoned:
> The Ancient Egyptians cut stone with an impressive level of precision. The Incas in South America did too. So much so that people sometimes claim that the Egyptians and the Incas used some kind of now-lost technology. But they most likely didn’t: they were just really good at cutting stone.
Yeah, but we're not that good at cutting stone anymore. So what gives? The explanation here is very lacking. They either had a technology that let them cut stone so well, or some special know-how (itself a form of technology, in my opinion) that enabled cutting stone so precisely.