Pretty sure that if you ask the cashier to exchange your gold nugget with a toothbrush you will have no problem proceeding with the transaction.

I'm pretty sure that if you try to buy a two dollar tube of toothpaste with a two dollar speck of gold, they'll say no thanks.

yup, I said a nugget.

You could walk in with a brand new Playstation 4 system and do the same thing.

That is an argument completely irrelevant to this discussion.

"You can't go into CVS and buy things with gold either."

Pedantry: US Gold eagle coins are actually legal tender US currency with a $50 face value.

So while it would be exceedingly foolish to treat an ounce of gold like a $50 coin, you could.

Where this becomes slightly interesting is the $10k limit on foreign currency declarations in international travel ... since these are $50 coins of US legal tender, you should be able to travel with 199 of them (worth about $200k) without declaring anything.

YMMV. IANAL.

I would be willing to bet you wouldn't get far trying to buy things at CVS with a Gold Eagle. It's likely they've never seen one and will assume you're trying to pull some kind of scam.

Not that I'd be willing to research the point with my own money.