FMF - Friends of Minerals Forum, discussion and message board

[Mathias]

Dear friends,

I got this specimen recently as part of 60 specimen parcel.

It was labeled "Tourmaline".

That's it.......no other information given.

Is there anybody out there who can help.....
To give me a clue where it might be from?

Thanks,

Mathias.

[Volkmar Stingl]

Looks like tourmalines from the Malkhan pegmatite field in Transbaikalia (at least the color). But I am not sure if it is really tourmaline. A picture of the top faces would help.

[Mathias]

Dear Volkmar,

Thanks for your reply. Here are some more pictures.
Perhaps it's not Tourmaline, it was just what was on the label.

Thanks,
Mathias

[Peter Lemkin]

The color is rare [but not impossible] for tourmaline. The parallel grooves on one side in one photo are sometimes indicative of tourmaline...but you have to do some work other than show photos. What is the hardness? streak? specific density? have a goniometer to measure the angles between faces?

[Tobi]

Peter is right, more information would be helpful to identify this crystal ...
But I also agree with Volkmar, according to the photos this is most likely rubellite, maybe from Malkhan pegmatite in Russia.

Regards
Tobi

[Jesse Fisher]

Exploitation of the Malkhan pegmatites is fairly recent. If it comes from an older collection, then this is not likely. It might help to know when and where the collection was assembled.

[Josele]

Another vote for tourmaline from Malkhan pegmatite field. This dark purple color is typical from this location.

[Mathias]

Thanks for everyone's input on this specimen.

I don't have a goniometer, and if I had one, it would be difficult to use since the specimen is glued on an acrylic display base.

I got this parcel of specimen from someone I met (as a vendor) at a small local mineral show (2019), he was selling relatively good specimens for too low prices, and I asked him if he had more at home. He gave me his address. Then, a few weeks later, I visited him (35 km driving from where I live) and since then I bought approximately 600 specimens from him (I went there some 15 times).

I bought all his international specimens, and what's left are 5 showcases with specimens from Becke Oese and Holzen, which he mined all by himself during 20 years. These 2 quarries mainly produced (both are no longer open for collecting) Calcite, Dolomite, Barite, Pyrite, Marcasite, Galena, Quartz, some Malachite. Many of which are really aesthetic specimens.

The person I bought these specimens from is between 70 and 80 of age and has no outlet for his minerals, and is no longer interested in collecting, for the past 10 years. So these specimens were just stored in showcases in a dark room.

I think I paid him more per specimen than a whole-collection-buyer would have done but less than the market price. This feels reasonable.

My wife always asks me "when will you stop buying all these minerals" because one day the same will happen to you. And she's probably right. And then I tell her that spending all this money on minerals pays back right now, in terms of fun.
The depreciation period is from now until I'm 80 (If i ever reach this age).

Thanks again for your help in identifying some of these specimens.
Most of the 600 specimen are on my Instagram account (NFS); marc.eggen

[Roger Warin]

I am 86 years old and tourmalines are my food.
Try to photograph your specimen in profile. You will get on a plane, the profile of your sample which you can then estimate the angle.
Mineralogy is better than sleeping pills ...

[Josele]

[Bob Morgan]

From the photos it sure looks to be tourmaline - striations on prism, three shallow pyramidal faces with a central triangular termination.
One way to check the pyramidal faces is to hold another similarly shaped crystal aside it and see if faces from both crystals reflect light at the same angle for all three faces.
This won't give you precise angle measurements, but it should confirm it's identity.

[Bob Carnein]

Be aware that tourmaline has various pyramids that intersect the prism faces at various angles, some steep, others shallow.

[Roger Warin]

And the two poles are different.

[Josele]

[Peter Lemkin]

I still think a hardness test would be one of the first things to do.