New grading system for Tanzanite?

Spooky
Posts: 408
Joined: 7 months ago

Re: New grading system for Tanzanite?

Post by Spooky » 2 months ago

Gemaholic wrote:
Fri Jan 10, 2020 8:16 am
JewelryQueen wrote:
Fri Jan 10, 2020 1:56 am
Can't remember where I heard about the new grading. Was at least 2 months ago but I know it wasn't at SLC. And yes I have heard that there is some type of cobalt treatment being used on Tanzanite but do not know any specifics about it. I'll bet some of the more educated ladies can give you the scoop. I love this forum!
'
Unfortunately the only way to know for sure is under a microscope or through chemical treatment.. I'd run a streak test on some of mine but it won't be accurate since streak tests are conducted in the rock's rough form (the powder created from rubbing the rock on the porcelain plate is how the streak color shows up and is determined).They can get in serious trouble for not disclosing they put a coating. It's one thing to heat treat tanzanite since that is accepted in the industry, but putting a coating on without telling customers is fraudulent. You can also try testing it in the sunlight to see if the pleochroism is present or looks faint. It's harder to do that test on pieces lower than AAA. I'll put some of mine under a microscope and let you know what I find. Stay tuned....
At GIA.edu they were using their microscopes as
well and that is how they found it. I’m curious
to see what you find.
3 x

Shawne
Posts: 5
Joined: 6 months ago

Re: New grading system for Tanzanite?

Post by Shawne » 2 months ago

I have contacted personal shopper and they have forwarded to QC department to find out what they are buying. But, I would be very curious to hear from you Moderator_Danielle to see if you can escalate this concern for us on the forum. I love tanzanite and would like the straight scoop on this, as do others here. Thank you.
4 x

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Gem Lover
Posts: 1104
Joined: 7 months ago

Re: New grading system for Tanzanite?

Post by Gem Lover » 2 months ago

I have a few of the color change fluorite from here and the color is nicer then my JTV ones, that would explain it if they are coated, if that is the case I will be furious.
3 x

CJM
Posts: 168
Joined: 6 months ago

Re: New grading system for Tanzanite?

Post by CJM » 2 months ago

Hmmm. Crickets I’m waiting for an answer. Seems important to me.
1 x

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OtherSideOfTheTracks
Posts: 1219
Joined: 4 months ago

Re: New grading system for Tanzanite?

Post by OtherSideOfTheTracks » 2 months ago

Gemaholic wrote:
Fri Jan 10, 2020 8:16 am
JewelryQueen wrote:
Fri Jan 10, 2020 1:56 am
Can't remember where I heard about the new grading. Was at least 2 months ago but I know it wasn't at SLC. And yes I have heard that there is some type of cobalt treatment being used on Tanzanite but do not know any specifics about it. I'll bet some of the more educated ladies can give you the scoop. I love this forum!
'
Unfortunately the only way to know for sure is under a microscope or through chemical treatment.. I'd run a streak test on some of mine but it won't be accurate since streak tests are conducted in the rock's rough form (the powder created from rubbing the rock on the porcelain plate is how the streak color shows up and is determined).They can get in serious trouble for not disclosing they put a coating. It's one thing to heat treat tanzanite since that is accepted in the industry, but putting a coating on without telling customers is fraudulent. You can also try testing it in the sunlight to see if the pleochroism is present or looks faint. It's harder to do that test on pieces lower than AAA. I'll put some of mine under a microscope and let you know what I find. Stay tuned....
Have you had a chance to look under the microscope? I don't own any tanzanite but am sure curious about the coating.
1 x

Gemaholic
Posts: 325
Joined: 3 months ago

Re: New grading system for Tanzanite?

Post by Gemaholic » 2 months ago

OtherSideOfTheTracks wrote:
Sat Jan 11, 2020 8:52 pm
Gemaholic wrote:
Fri Jan 10, 2020 8:16 am
JewelryQueen wrote:
Fri Jan 10, 2020 1:56 am
Can't remember where I heard about the new grading. Was at least 2 months ago but I know it wasn't at SLC. And yes I have heard that there is some type of cobalt treatment being used on Tanzanite but do not know any specifics about it. I'll bet some of the more educated ladies can give you the scoop. I love this forum!
'
Unfortunately the only way to know for sure is under a microscope or through chemical treatment.. I'd run a streak test on some of mine but it won't be accurate since streak tests are conducted in the rock's rough form (the powder created from rubbing the rock on the porcelain plate is how the streak color shows up and is determined).They can get in serious trouble for not disclosing they put a coating. It's one thing to heat treat tanzanite since that is accepted in the industry, but putting a coating on without telling customers is fraudulent. You can also try testing it in the sunlight to see if the pleochroism is present or looks faint. It's harder to do that test on pieces lower than AAA. I'll put some of mine under a microscope and let you know what I find. Stay tuned....
Have you had a chance to look under the microscope? I don't own any tanzanite but am sure curious about the coating.
Let me see if I can do it today. I've been running around the past couple of days like crazy. Though it won't take long, I don't want to rush it since I want to really inspect it.
3 x

Gemaholic
Posts: 325
Joined: 3 months ago

Re: New grading system for Tanzanite?

Post by Gemaholic » 2 months ago

CJM wrote:
Sat Jan 11, 2020 7:23 pm
Hmmm. Crickets I’m waiting for an answer. Seems important to me.
I checked under a microscope and posted a separate thread called Tanzanite Coatings just in case people don't see my response here.
2 x

Shawne
Posts: 5
Joined: 6 months ago

Re: New grading system for Tanzanite?

Post by Shawne » 2 months ago

moderator_Danielle, would you please respond to the forum about this topic? It is important enough to those of us who buy tanzanites, some very expensive ones, to get a definitive answer from the official source. I did run this up the chain and have heard nothing back. Can you please respond? Thank you.
2 x

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RS
Posts: 3832
Joined: 6 months ago

Re: New grading system for Tanzanite?

Post by RS » 2 months ago

Shawne wrote:
Tue Jan 14, 2020 12:04 am
moderator_Danielle, would you please respond to the forum about this topic? It is important enough to those of us who buy tanzanites, some very expensive ones, to get a definitive answer from the official source. I did run this up the chain and have heard nothing back. Can you please respond? Thank you.
@Moderator_Danielle
2 x

User avatar
Moderator_Danielle
Posts: 613
Joined: 7 months ago

Re: New grading system for Tanzanite?

Post by Moderator_Danielle » 2 months ago

JewelryQueen wrote:
Thu Jan 09, 2020 11:59 pm
A while back I heard a rumor that Tanzanite was going to be graded on a numerical system. 1 - 100? if I remember right. Haven't heard anything since. Anybody else hear anything about this?
Hello,

I do not have confirmation form anyone that the tanzanite grading system is changing. Nevertheless, I will double check and revert back ASAP.
3 x