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Identification of rock


I have recently started polishing gemstones and rocks as a hobby. Can anyone please identify this material? It has red material in it as well - like jasper


Hello everybody,
Can somebody help me on that stone.
I have baught it as an emerald.
After testing it with Peesidium Gem Indicator it appears 1/5 as tourmaline or emerald and 4/5 as glass.
Could you provide you opinion on that.
I baught it in west Africa.
Waiting for your opinions,


Hi Antoine, if you could use a spectroscope you could in a minute know if it was an emerald or another gem. Also a Specific gravity test would get you closer to what the gem is. if you polished one side and did an RI this would also help Identify the gem. I would doubt if it is Emerald just by looking at your photo, I would hazard a guess at Tourmaline. But no one will positively identify a gem from a photo, unless it is a distinct Crystal formation then that may be possible. Hope you did not pay a large amount of money for it. It is not wise to purchase gems if you cannot do any field tests on the gem to have a reasonable idea on its identity.

Regards Syd


Oh and I did not add one of the easiest field test for emerald, just use the Chelsea filter and if it turns from green to red you can then look at the gem as containing chromium, will not tell you if the gem is synthetic or natural, but it is a good start.

regards Syd


Hello Syd,
Thanks very much for your reply, it is very kind of you.
Since last time I have been brought many other green stone and the gem indicator (presidium) indicates 3 possibility according to the color aquamarine emerald or glass.
I will for sure try the test you advise me.
Thanks again,


Seems like a really strange color for emerald…


Seems like a really strange color for emerald…


Hey Gents,
Thanks a lot for your commitment.
This gem Society is great.
Them Green stones after tests and visualise inspection by professionals appears to be green tourmaline.
Thanks again to all of you.


Hi Jeweldzine, I see no one has had a guess at your initial question about the spotted green gem, I could be way off the mark but to me it looks similar to Riolite, see attached


technically emerald has a higher Mohs hardness of 7.5-8 -glass mohs hardnes 6.5-7- hardnes tourmaline 7,7.5 maybe scratch test try it?Hallo


It kinda looks like Kambama Jasper