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Diffused blue spinel

T L

Super_Ideal_Rock
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Sep 20, 2008
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25,217
I noticed a very blue spinel online, and the treatment was disclosed, diffusion!!

I then searched “blue spinel diffusion” and this GIA article from 2015 popped up. Maybe everyone knows about this already, and I’m late to the game, but it’s a new thing to worry about, especially if you’re buying what you think are cobalt spinels.

https://www.gia.edu/gia-news-research/cobalt-diffusion-natural-spinel-report
 

arkieb1

Ideal_Rock
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May 11, 2012
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Yep diffused blue spinel have been for sale at the markets for a while now..... They are messing with reds and pinks now (as they become more difficult to find) as well.
 

Mrs_Strizzle

Brilliant_Rock
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Jun 14, 2018
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15ish years ago when I discovered spinel one of the main draws to me was that it wasn't treated. So disappointing to see it bastardized.
 

lovedogs

Super_Ideal_Rock
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Jul 31, 2014
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18,271
I noticed a very blue spinel online, and the treatment was disclosed, diffusion!!

I then searched “blue spinel diffusion” and this GIA article from 2015 popped up. Maybe everyone knows about this already, and I’m late to the game, but it’s a new thing to worry about, especially if you’re buying what you think are cobalt spinels.

https://www.gia.edu/gia-news-research/cobalt-diffusion-natural-spinel-report
Since I love this color, I am totally excited about this. Obviously as long as the treatment is disclosed. Lying or selling it as something it isn't is not ok.
 

arkieb1

Ideal_Rock
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Since I love this color, I am totally excited about this. Obviously as long as the treatment is disclosed. Lying or selling it as something it isn't is not ok.

The issue is that if you go to the markets in countries like Vietnam, Burma and Thailand they used to salt parcels of both cut stones and rough with synthetic cobalts so a mix, so that unsuspecting buyers would pay for a load of rubbish, now they are swapping out the parcels with cheaper diffused ones, so if you are a tourist and you don't know the difference it's a minefield....

Of course there are a few dishonest vendors that don't declare treatments too but most of the good ones do.
 

lovedogs

Super_Ideal_Rock
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Jul 31, 2014
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18,271
The issue is that if you go to the markets in countries like Vietnam, Burma and Thailand they used to salt parcels of both cut stones and rough with synthetic cobalts so a mix so that unsuspecting buyers would pay for a load of rubbish, now they are swapping out cheap stones with diffused ones, so if you are a tourist and you don't know the difference it's a minefield....

Of course there are a few dishonest vendors that don't declare treatments too but most of the good ones do.
Yeah, which is awful.
 

voce

Ideal_Rock
Joined
May 13, 2018
Messages
5,161
Unless I know it's old stock and trust the person, I would even be afraid of a good vendor's source passing on a diffused gem, so the trusted vendor sells you a dud. As prices skyrocket the incentive for miners to be dishonest goes up greatly.
 

arkieb1

Ideal_Rock
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Unless I know it's old stock and trust the person, I would even be afraid of a good vendor's source passing on a diffused gem, so the trusted vendor sells you a dud. As prices skyrocket the incentive for miners to be dishonest goes up greatly.

The good vendors know what they are buying, where to buy it and use equipment to look closely at all the stones, that's why it's worth paying the middle man so to speak for the time and effort to sort out what you are getting.

I have people all the time that are not stone people on IG message me thinking I can magically get large inexpensive cobalts and jedi spinels, I think to myself I'm a collector not a magician..... I don't think they have a clue how difficult these stones are to get let alone clean or in sizes above a carat...
 

Lisa Loves Shiny

Ideal_Rock
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Nov 1, 2007
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4,729
I am very suspicious of red and blue spinels being sold now. I would want a reputable lab report on any spinel that cost a significant amount of money.
 

arkieb1

Ideal_Rock
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May 11, 2012
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I am very suspicious of red and blue spinels being sold now. I would want a reputable lab report on any spinel that cost a significant amount of money.

Most spinels all colours in general are still untreated, it's the rare stuff like Jedi reds and pinks that are often oiled the miners themselves in some places soak them in things like cooking oil to try and make the clarity look better. And cobalts can be diffused. The rarer and more expensive the stones coupled with high demand means they are more likely to be messed with.

The key is buying them from people you either know or trusted vendors, I see so many people looking for unrealistic bargains on places like Ebay and GemAuctions, etc - and although it's common sense, if it's too good to be true then always think carefully..... so many new people just go for the bargain without actually thinking out why something is a lower price.
 
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