Tundra/Tunduru/Tundura Sapphire?

Hi All, could someone please tell me if there is such a thing as Tundra/Tunduru/Tundura Sapphire or are they just garnets/other gemstones. I would like to purchase some but I want to know what they really are? Any help you can give would be greatly appreciated. Thank you, Di

Yes there is sapphires from Tunduru, Tanzania. Tunduru is famous for producing lots of gems including sapphire, spinel, kornerupine, garnets, etc. Just be wary of someone trying to pass off something else from Tunduru as a sapphire but of course thats the case with any gem material from anyplace. As a side note: There is a Greenish to red/violet shift that occurs in very rare sapphires that have vanadium in addition to chromium as a coloring chromophore. To my knowledge they are only found in a few places and Tunduru being one of them



Edited 1 time(s). Last edit at 04/06/2011 03:10PM by Jason Barrett.

So they wouldnt be brown, orange, rhodolite garnet colour, yellow in colour then? Its just that i have seen strands of these on etsy and I cant get a specific answer from any of the sellers

They can be any color possible just about. You said "strand" so you are talking about beads or bead quality stones?

Yes a strand of beads...opps is that a dirty word around here then?

Hi Diane,

How large are the beads? Faceted or polished chip style? A picture would be helpful.

If I have time much later this evening I will try and post pictures of Tunduru rough as well as some faceted stones that you could compare.

regards,
stephanie

tiny faceted rondelles, I wanted to purchase them before of the different colours, thought they would be great for clusters for earrings, but I dont want to purchase a strand if I dont really know what they are. To me they look like garnets, smoky quartz, citrine and Iolite with a couple of prasiolite mixed in, but who knows

Check out these pics, perhaps you can enlighten me because i really dont know and neither it seems to the sellers

I think you have answered your own question.

The second pic looks more like pink and green tourmaline or green tourmaline and garnet IMO.


regards,
stephanie

Stephanie,

Tunduru Sapphires (beads and gemstones) are commonly known to be heat treated with beryllium, especially the golden yellow, orange, and red ones to enhance their color. The color is usually only "skin deep," so they may revert back to their original color with "wear and tear." If you have some beads or gems to spare, I would break some open and see what's on the inside. Beryllium heat treatment of these sapphires is commonly done in Thailand. You might not see the word "beryllium" used in the treatment description by unscrupulous sellers, just the word "heated." Here are some links to discussions regarding the "shenanigans" going on with Tunduru sapphires.

[gemologyonline.com]
[cs.beadandbutton.com]
[www.mindat.org]

Jan

Jan, I think you meant to direct the links to Diane.

I am aware of heat treatments etc, but I still don't think those are sapphires, heat treatment or not, in my humble opinion.

regards,
stephanie

In my opinion they will be BE(like Jan said..especially the yellows and oranges) treated sapphires. Bead quality sapphires are a dime a dozen and won't cost anymore wholesale than the other minerals garnet, citrine, smokey, tourmaline, etc.. Not many people are going to fake bead quality material because it's low quality to begin with and the cost/benefit is not really there. With most beads your main worry is dying and treatments. It cost me more to order bead quality tourmaline than it does sapphires or rubies



Edited 1 time(s). Last edit at 04/06/2011 07:51PM by Jason Barrett.

Jason is right. They are more then likely Be Treated. But there is some corrections that are needed. Be Treatment is a diffusion process not just typical heating. Also this method of treatment is NOT just on the surface, it goes all the way through with sometimes leaving a small color core. The colors are permanent and will NOT fade NOR wear off. Beryllium Treatment can produce almost any color now, typically golden yellow, red, oranges, padparadscha, blue, green, and even purple. Yellow/gold, if show any signs of heat at all, even low, most Gemologists and labs consider them Be treated. Thee only way to be sure is with either XRDF or LIBS testing typically. But a proper microscopic and immersion exam by an experienced Gemologist can often give some telltale signs to the treatment.

I also don't believe these are Tunduru sapphires, but most likely Songea. But since most Songea sapphires are Beryllium treated now, many sellers try to pass them off as Tunduru and/or Umba material, because these produce natural vivid colors as well. Tunduru do tend to not be as vivid as Umba material though.

The first stand I can almost guarantee are Beryllium treated. The second probably are, but not as obvious. Also, most beads are Beryllium treated as well as stabilized or clarity enhanced as well. Lots of Beryllium treated glass filled sapphire beads have been flooding the market as well as even some glass filled faceted sapphire gemstones! These would be a dime a dozen! For untreated faceted sapphire beads, you will pay same price per carat almost as faceted gemstones, if cheaper, then there are treatments involved.

But keep in mind, Beryllium treatment is pretty well accepted now that the color is all the way through, completely stable, and do not wear off nor fade.

------------------------------------------------------
Registered Gemologist
Research Gemologist
Rockhound/Cutter/Collector
Club President/Owner

Sorry Diane and Stephanie! I think my brain has the hiccups ... today :S

Jamey,

I didn't know that Be Heating had progressed as far as altering the entire stone's color and being stable. Thanks for that info! I've been away from my minerals, gemstones, home, and the internet for a while. Time to do some reading and catching up!

Jan

No worries, Jan, I knew what you meant ;)

Thanks Jamey for that explanation as Jan noted.

regards,
stephanie

Thank you everyone, Im still not clear what they are but I didnt realize that just about everything out there is heat treated or has had something done to it which is a great pity really because do you really know what you are buying? Well you all would because you know your stuff but the likes of me...I have got no chance.

Here is a photo of some alluvial Tunduru rough and faceted stones. These are all natural, not treated, no heat, nothing.

The rough is mainly sapphire, spinel and chrysoberyl with some garnet. The amount shown is 100 cts.

Four jars of faceted Tunduru sapphires and one of Songea (2.5mm), the Songeas are in the front right corner and these have paler shades. Perhaps that is why they make for more vivid treated stones.

Sorry for the indoor lighting.





Edited 1 time(s). Last edit at 04/07/2011 05:16AM by Stephanie Martin.

Jan,
Yes Be Treatment has been to the core now for quite some time. They are even doing some at much lower temps then they used to, like with the gold/yellow, which makes it very difficult to tell. This is why they have become much more accepted and prices have greatly increased on the material as well. Standard diffusion only penetrates into the surface and if the stone gets chipped or scratched up the color will be lost upon recutting. Be Treated ones can typically even be recut now. :).

Diane,
There are still lots of untreated materials out there, but they carry a premium price tag. The easiest way to know what you are getting is to find a trusted source! Buy from China you will get all kinds of junk from flat out fakes to dyed to synthetics to anything but the real thing, lol. Thailand is not much better anymore, especially with beads! Odds are as well, if you buy cheaply on Ebay you will also end up with something other then what you actually purchased, sadly. :(. This is one area where if something seems to good to be true and too cheaply priced, it is! There is a reason if the material in question is a fraction in price compared to that in a real valid store! Same goes for TV, don;t fall for the BS, "we buy in bulk so we just get it cheaper", load of malarkey, lol. There are only a few things that make a material cheaper:
1. Treatments
2. Poor cutting and lower quality polishes
3. Not as advertised, meaning it is a synthetic, simulant, reconstituted and/or dyed, etc.
4. Did I already mention treatments and poor cutting/polishing? ;)

But do NOT just assume that because a seller is in the USA, or not in an Asian country, that their wares are as advertised! Many USA sellers simply buy from the overseas scammers and resell the garbage at a profit, :/ Investigate your seller, ask questions about credentials... i.e. are they a Gemologist? How many years experience? etc. Ask about possible treatments and see how they respond. Scammers will immediately get on the defensive and flip out typically, lol.

Side note, watch out for the latest scams all over Ebay and such! Girasol... It is NOT blue opal, it is NOT gem silica, it is NOT anything super super rare... What it actually is, is nothing but simple old quartz with a twist. You know the nice star rose quartz you see out there in cabochons? This is the same exact thing, except it does not have the same chromophore(coloring component) and is white. It is nothing more then white star quartz or white quartz with an asterism, your choice. But it is NOT blue opal, NOT Girasol(which is a type of golden flash opal), nor any kind of gem silica, lol.

------------------------------------------------------
Registered Gemologist
Research Gemologist
Rockhound/Cutter/Collector
Club President/Owner

Great additional info there, Jamey. I did not know about the Girasol. Sweet, thanks for the heads up.