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 Post subject: Native colors in moissanite?
PostPosted: Sun Apr 08, 2018 1:37 pm 
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Does anyone know the full color range of moissanite where the color permeates the stone entirely (not a surface treatment)? What elements are responsible?

https://www.mindat.org/min-2743.html
The mindat page for moissanite lists colors as "Green, black, blue, colourless, green yellow, yellow". A browse on ebay for Indian stones backs up that statement (imo Indian moissanite is unlikely to be surface-enhanced due to the low price range and high volumes these sellers deal in). There are also gray and brown stones available on ebay.

Interestingly, Charles and Colvard only sells green in addition to colorless moissanite.


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 Post subject: Re: Native colors in moissanite?
PostPosted: Sun Apr 08, 2018 4:25 pm 
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I don't know that the Indian ones are more lilely to be surface treated. Colored moissanite in some tones is apparently much easier to make than colorless. My dad picked up some greyish teal blue ones for cheap that were quite attractive, though probably not in great demand.

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 Post subject: Re: Native colors in moissanite?
PostPosted: Mon Apr 09, 2018 8:56 pm 
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Stephen Challener wrote:
I don't know that the Indian ones are more lilely to be surface treated.


What I meant in my original post is Indian moissanite is less likely to be surface-treated for color. Sorry for the confusion :)


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 Post subject: Re: Native colors in moissanite?
PostPosted: Thu Apr 12, 2018 2:07 pm 
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I've found some picures of moisssanite colors attributed to Charles Colvard.
They were NOT made by Charles and Colvard.

The only fancy color they sell is green. And, never loose, always mounted.
Image

The colors which are probably moissanite made by someone:
Image

The pinks online, are misleading at best.
https://www.ebay.com/itm/Charles-Colvar ... 0005.m1851
I just hung up the phone with C&C....They do not make pink moissanite.


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 Post subject: Re: Native colors in moissanite?
PostPosted: Fri Apr 13, 2018 10:55 am 
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Barbra Voltaire wrote:
I've found some picures of moisssanite colors attributed to Charles Colvard.
They were NOT made by Charles and Colvard.

The only fancy color they sell is green. And, never loose, always mounted.

I just hung up the phone with C&C....They do not make pink moissanite.


Thanks for following up Barbra!! I've read that C&C used to sell gray moissanite but apparently (according to the article linked below) couldn't make the production process predictable enough for it to be worth the trouble.

I also found the original patent from C&C which contained this "recipe" table for different colors. I didn't know it involved different polymorphs of SiC in addition to doping agents! Really interesting stuff, shame there isn't more publicly available information but I expect that to change since the C&C patent expired and all the Chinese and Indian manufacturers are now getting in on the game.

Colorless-- 6H SiC, Undoped
Colorless-- 4H SiC, Undoped
Blue-- 6H SiC, Al-doped
Purple-- 6H SiC, High Al-doped
Purple-- 24R SiC, N-doped
Green-- 6H SiC, N-doped
Yellow-- 3C SiC, Undoped
Yellow-Green-- 3C SiC, N-doped
Red-- 27R SiC, N-doped
Light Brown-- 4H SiC, Low N-doped
Yellow-Orange-- 8H SiC, N-doped

Source: https://patents.google.com/patent/US5723391
https://www.kristincoffin.com/blogs/new ... in-jewelry


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 Post subject: Re: Native colors in moissanite?
PostPosted: Sun Apr 15, 2018 8:24 pm 
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I've got a bunch of pieces of moissanite rough, from earlier and more recent production runs, and Dr. Bulatov was showing off some of his larger ingots this year at Tucson. Yellows/browns are considered a colour defect, but it's comparatively easy to make those. It's also fairly easy to make stones that are greenish-blue (or to either end of the spectrum), but those tend to run dark (I don't have a reason why yet...).


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