What did I buy from this thai vendor?

[bbj123]

Hi! I'm a newbie and not at all knowledgeable in terms of stones. I bought this "green amethyst" from a thai vendor on ebay.
I've already read about green amethyst beind a rarity and that most stones are somehow treated. The vendor usually discloses if the stones are treated or not, and he states "unheated" on the ring's description. The stone is very big and the price was cheap, I have no idea what did I just buy - is this an artificially coloured stone? Maybe someone here could give me some detailed information? Thank you

 

[RSargent]

There are others who are more educated but this may be a prasiolite ... A heated amethyst.

 

[minousbijoux]

Prasiolite sounds exactly right.

 

[Dioptase]

Hi! I'm a newbie and not at all knowledgeable in terms of stones. I bought this "green amethyst" from a thai vendor on ebay.
I've already read about green amethyst beind a rarity and that most stones are somehow treated. The vendor usually discloses if the stones are treated or not, and he states "unheated" on the ring's description.

Naturally occuring prasiolite is indeed rare, Mindat only reports a few locations worldwide.

You can get prasiolite by gamma rays irradiation of colorless quartz (not all) or by heating amethyst from a few locations (like Montezuma, Brazil).
You can tell them apart with a chealsea filter: the irradiated one turns reddish while the heated material stays green.

From what I know, you can't determine if the prasiolite has been naturally or artificially heated.

 

[LoversKites]

Could be glass.

 

[chrono]

It is probably prasiolite, which is not expensive and not rare. The vendor spoke the truth in a roundabout way; the stone probably isn't heated but is irradiated.