How are the crystals colored? Are any chemicals used, such as chromium?
Thank you for asking! I passed the question to the manufacturer and will notify you when the answer arrives.
I am sorry but I did not find out a lot more. Maggie, the artist buys the crystals at the gem show and they are already treated. She says: "I was advised that the rainbow treatment is titanium but I can't confirm which ingredients are used in the compound. I will try to get more info and will let you know if I come up with anything."