They should have never told a soul. Maybe sold a few, one by one as numismatics. Nobody would have been the wiser. Melt and sell the rest. Go a step further. When you melt it, drop the molten into a bath of mud and water. Create “nuggets” that you will then discover over many years.
Nuggets aren’t that pure are they?
Melting them down, as many here suggest, is about as dumb as it gets.
The problem is at least twofold. One, some of these coins are very rare and desirable to collectors, and also - in practically “mint” condition. This puts their value far in excess of their value in terms of gold. Common date $20 gold coins in average condition trade at or near fhe “spot” price of gold. So they would be taking coins worth $100,000, $300,000 (or more) and rendering them down to an unrecognizeable lump technically worth about $1,500.
Except, that isn’t how it works.
If you show up to a bullion dealer with an unrecognizeable lump, he doesn’t pay anywhere near what it’s really worth. He knows its gold, and has a good idea on purity, but unlike recognized coins and bars it needs to be assayed. Might get $500 or so. Stupid!
Good problem to have. Even selling a few at a time, would eventually invite suspicion. “Where are you getting these!?” LOL. These coins were very well preserved, and there just aren’t many of these high dollar rarities floating around in the wild.