TASART, your knowledge of these stones is truly amazing. To pinpoint the age AND the mine? I think u are right about several things, gems were replaced, they arent turquoise, certainly not all, if any and they certainly do look like Chrysocolla. Now why your fascination with this particular stone? It is eccentric and beautiful that is for sure. I wanted to look at some of your beads but you dont have any listed~! Also, I'm not being lazy well, yes I am but the Amazonite. What is it and yes I'll look it up but would love to hear it from the horses mouth, is that a form of turqouise? and given you guess Colorodo 1876 wouldnt that in itself make it valuable. Incredible work, I'm in awe- and slightly nauseous since it is obvious how little I know about gemstones as well as this piece. (I can see the ad write up now when I go to sell it. LOL, is all I can say.) "Well, it could be [xxxx] but its probably not from [xyz date] but its probably not that either, although there is a good chance the artist did this [xyzp] but I cant be sure. In fact I'm not sure of anything!! So if you like it just buy it. Heck it might contain the next Hope Diamond for all that we know." (With my luck it would and I'd have sold it for $200.00)