Newsweek article with my comments at end. https://www.newsweek.com/texas-mexi...-mysterious-growing-substance-history-1934640
You should have had a word with the Ancient Coin guys. It sounds like Bronze Disease to me. Bronze disease is an irreversible and nearly inexorable corrosion process that occurs when chlorides come into contact with bronze or other copper-bearing alloys. It can occur as both a dark green coating, or as a much lighter whitish fuzzy or furry green coating. Here is a treatment for Bronze Disease on coins. Dissolve benzotriazole in ethanol (6-7% solution) and soak the coin from 1 hour to 2 days. Following this step, move the coin back into distilled water for 1 week to rest it.
Thanks. One issue is that this object was cast by amateurs in a backyard or something. Only the bigwigs at Alamo are allowed to see the metal analysis. However I suspect the makers were aiming for brass but may have put other Stuff in. Zinc with contaminants such as lead will exude “zinc pest” which for example.destroys many older die cast toys. But they found Formic acid dissolves the stuff. They call it a “carbonate” but I haven’t yet seen the other part of the compound.
OMG. I think that was the first real horror movie I saw. I was 5. It didn't really scare me. Then I saw the Mole People when I was 8. I still won't step on a manhole cover or sidewalk grate and I'm 75!
I thought he was talking about Ants. Horror movies don't scare me too much; real life... real life scares me.