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Fakes & FraudsTundra/Tunduru/Tundura Sapphire?

6th Apr 2011 14:30 UTCAnonymous User

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

6th Apr 2011 15:59 UTCAnonymous User

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

6th Apr 2011 16:04 UTCAnonymous User

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

6th Apr 2011 16:12 UTCAnonymous User

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

6th Apr 2011 16:20 UTCAnonymous User

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

6th Apr 2011 17:16 UTCStephanie Martin

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

6th Apr 2011 17:29 UTCAnonymous User

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

6th Apr 2011 19:07 UTCStephanie Martin

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

6th Apr 2011 20:23 UTCJan Styer-Gold

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.

http://gemologyonline.com/Forum/phpBB2/viewtopic.php?t=5018

http://cs.beadandbutton.com/bnbcs/forums/p/6664/31369.aspx

http://www.mindat.org/mesg-55-89859.html

Jan

6th Apr 2011 20:38 UTCStephanie Martin

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

6th Apr 2011 20:49 UTCAnonymous User

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

6th Apr 2011 21:17 UTCJamey Swisher

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.

6th Apr 2011 21:39 UTCJan Styer-Gold

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

6th Apr 2011 21:48 UTCStephanie Martin

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

Thanks Jamey for that explanation as Jan noted.

regards,

stephanie

6th Apr 2011 22:24 UTCAnonymous User

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.

7th Apr 2011 06:14 UTCStephanie Martin

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.

7th Apr 2011 06:43 UTCJamey Swisher

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.

7th Apr 2011 17:58 UTCAnonymous User

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

10th Nov 2013 19:33 UTCJulia

Great information on this board. So please, can you tell me where to look to get good quality, real stones? I have a guy I trust very much who travels to Asia regularly and brings back gorgeous stones, pearls and beads. He is my only good source though, and if he doesn't currently have something I want, I'm just out. I take great pride in my work and want to be sure I'm giving my client exactly what I tell them it is.

11th Nov 2013 02:04 UTCOwen Lewis

You don't say but it sounds as though you want rough of cuttable quality? Talk to some of the advertisers on this board and see if what they have and their prices will suit you. Or try one of the specialist faceters' forums.

If you really want the best deals and to be sure of what you are selling to your customers, you *must* learn to identify and grade for yourself. That means study. some equipment - and experience. It includes being able to spot (most of) the Heinz 57 enhancement treatments that are now used routinely on many stones.it also means knowing and understanding those treatments which are commonplace and undetectable for practical purposes.

You cannot expect a dealer to have checked every piece of the hundreds of kilos of rough they will sell every year. I have a friend who found a taaffeite in a five buck bag of spinels bought from a Sri Lankan dealer. He's been dining out on the story ever since :-)

11th Nov 2013 06:17 UTCRock Currier Expert

Julia,

Where do you live? What is your work? Go you make jewelry? Out of faceted gems? Cut and polished lapidary materials? Have you the means to travel?

3rd Jun 2015 20:16 UTCBecky Noland

Many years ago, I purchased a one-carat loose stone described as an unheated/untreated tundura sapphire. It was absolutely lovely. In the sun, there was a strong deep blue color, but it also had flashes of red visible as the stone was rotated. The stone itself is transparant This was at the time I was hearing the fuss begin about Tanzanite, and I found out that this Tundura sapphire was from the same region as that stone. I chose the sapphire for it's hardness and durability over the tanzanite and was very pleased. I had the stone set in a white gold solitare ring with six prongs, and the amount of metal around the stone absolutely killed the life and color flash of the sapphire. Only if I get it in the exact right lighting is it still visible....but I know what is in there! My question is this: What is this stone worth today (ballpark) and is it worth more if I removed it from the setting?

3rd Jun 2015 21:32 UTCBob Harman

BECKY, Since your question concerns the stone's value, this posting should have been put on the valuation thread, but no matter. Your photos and description are of such poor quality that even a ball park guess is not possible. Facetted stones must be evaluated by an ethical and competent jeweler or gemologist. They will know of the exact type of stone, exact size (in carats), and evaluate the color, clarity, cut, and quality. None of this is apparent in your photos. Not even the setting cannot be realistically evaluated as the amount of metal and its type needs in person expert evaluation. CHEERS…….BOB

5th Jun 2015 18:17 UTCRock Currier Expert

I think you might find it difficult to sell for more than $100.

26th Aug 2017 14:41 UTCAntonia369

Hello - I am curious about an Etsy listing for strands of Tunduru GARNETS (they have listed them as Tundro, which I presume is a spelling or phonetic error). The seller is in India. After reading all the posts for this thread (so interesting -- thank you everyone!), I am curious if such a stone exists. Given the provenance of the Tunduru Sapphires as discussed here, I see that garnets are also found in that area. But I've never heard of a Tunduru garnet and would like input from this forum. I've downloaded one of their listing photos which will hopefully be useful. The price per strand is very inexpensive ($9.95 for 13"). I love this color mix/range, and for the price I don't mind in the end what stone it is. Based on the previous comments here I am thinking of asking the seller if they know what type of treatment the stones have undergone, also to see if they are on their game or not.

Thank you in advance for any input.

26th Aug 2017 15:26 UTCBob Harman

ANTONIA, While I am no expert, those definitely look plastic or similar man made stuff. In my opinion, definitely not natural. CHEERS.....BOB

26th Aug 2017 15:48 UTCAntonia369

Hello Bob and thank you for your prompt reply....

I have had previous transactions with this seller (other stone beads): lapis, moss aquamarine and andalusite, and then subsequently had them checked by my local jeweler who confirmed their authenticity. So I know he doesn't sell plastic. (Bad photo representation I guess....) :-) Since posting here, I actually wrote and already received information from the seller, who said the stones are mixed untreated garnets -- so I'm thinking grossular, hessonite, almandine and so forth. Indeed, he wrote me that he indicated them as "Tundra" as a reference to the color variations found in stones mined in Tunduru, Tanzania.

Being that my original question here was the use of Tundra for garnets, I would have to say that I am satisfied with the seller's explanation.

6th Jun 2018 22:02 UTCJohn Almasi

Tunduru Sapphire is not a bead. In 1995, along with the alexandrite strike in Tunduru, a wealth of fine blue naturally clear sapphires came to light. Larger sapphires, called Gauda in the region and ranging up to 2-3 grams in size were also there. These were suitable for heat-treating into fine blue sapphires. The rough has long since been off of the market, due to scarcity of supply, but if you have one of the nice blues, it becomes more valuable each year. The top color usually was Blue/Purple 7/5.

7th Jun 2018 23:29 UTCA. M.

Antonia369, you have real stones. I bought a similar in gem show in late 1990s.

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