I was at Neimans today and saw the new Batu Kali bracelets from John Hardy. They come in your choice of three completely unnatural gemstones: dark blue topaz, dark green topaz and bright / dark pink topaz. So....I the green! It's a stunner! Really amazing. It's like the perfect emerald WOULD look...only....uh...HOW did they get that color? My gemstone guide "Colored Gemstones" by Antoinette Matlins notes that green topaz comes into this world either by nuclear irradiation (in a commerical nuclear reactor) - and is not stable over time - or is surface treated - the green sits only on the surface of the stone. But, it is stable, it's just not really a green stone. It's an optical illusion. Choices, choices... The blue topaz is almost certainly irradiated in a nuclear reactor while the pink is probably just heated - and is color stable. Whew! Does that sound right to anyone else? Of course the NM jewelry girl had no idea about any of this. I didn't even bother because when I asked if the stones were natural (which of course they COULDN'T be) she said she 'thought so'. Ugh. I emailed a question to John Hardy Customer Service thru their website and we'll see how technical they can/will get. I'll post the answer here if it's interesting. Despite my concerns I should add that I LOVE that green bracelet...if you had SEEN it. I'm buying it as long as I can get SOME assurance that it's color stable and not radioactive. Sorry for the long post! Please let me know if you have any info / opinions! Thanks!