The commonly faked or enhanced stone I talked about previously was turquoise, where one of the main purposes of the chemical treatment is to prevent the stone from changing color as it ages.
For the widely available “peacock ore,” the opposite is true. Peacock ore is actually chalcopyrite, or more rarely, the closely-related mineral bornite, or some combination of both. Chalcopyrite is a copper iron sulfide that starts out a brassy gold similar to pyrite and, over time and exposure to air, develops a tarnish that can evolve into a variety of interesting colors. So in this case, shiny freshly-mined chalcopyrite has fewer commercial possibilities than lying-around-for-a-while tarnished chalcopyrite.
The solution to this marketing quandry? It’s acid-washed. Or heat-treated. Or both. Only the people who do it know for sure, but won’t say since they don’t want competition. The result is “peacock ore,” with shiny spots of every color you can imagine, but also (to me at least) very unnatural-looking. The stuff is ubiquitous in gift shops, but if you can’t recall it offhand, search eBay for “peacock ore.”
What’s interesting is that no one ever ever ever ever EVER mentions that peacock ore is “enhanced.” You’d expect that from souvenir shops, but it also applies to metaphysical stores selling these for “natural healing,” and even to online rock shops that are selling “specimens.” Here’s part of a thread from a rockhound mailing list that started with someone asking how to do it.
Personally, I’ll stick with natural stones for my natural healing or natural specimens for my display cabinet. I’m happy to watch them change on their own.
Chalcopyrite (left) and bornite (right). With a loupe I can see a little of the other in each one, so in that way they remind me of the yin and yang symbol.