July 25-29: FRANKLIN, NORTH CAROLINA: Annual show; Bellpoint Promotions ; Echo Valley Showplace; Wed. 9-6, Thu. 9-6, Fri. 9-6, Sat. 9-6
Welcome to the GemologyOnline.com Forum
A non-profit Forum for the exchange of gemological ideas
It is currently Sun Jul 22, 2018 4:06 pm

All times are UTC - 4 hours




Post new topic Reply to topic  [ 6 posts ] 
Author Message
 Post subject: Native colors in moissanite?
PostPosted: Sun Apr 08, 2018 1:37 pm 
Offline
Established Member

Joined: Sat Apr 07, 2018 2:44 pm
Posts: 11
Location: New York, New York
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.


Top
 Profile  
Reply with quote  
 Post subject: Re: Native colors in moissanite?
PostPosted: Sun Apr 08, 2018 4:25 pm 
Offline
Moderator
User avatar

Joined: Mon Apr 02, 2012 9:31 pm
Posts: 2857
Location: North Carolina
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.


Top
 Profile  
Reply with quote  
 Post subject: Re: Native colors in moissanite?
PostPosted: Mon Apr 09, 2018 8:56 pm 
Offline
Established Member

Joined: Sat Apr 07, 2018 2:44 pm
Posts: 11
Location: New York, New York
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 :)


Top
 Profile  
Reply with quote  
 Post subject: Re: Native colors in moissanite?
PostPosted: Thu Apr 12, 2018 2:07 pm 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 18833
Location: San Francisco
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.


Top
 Profile  
Reply with quote  
 Post subject: Re: Native colors in moissanite?
PostPosted: Fri Apr 13, 2018 10:55 am 
Offline
Established Member

Joined: Sat Apr 07, 2018 2:44 pm
Posts: 11
Location: New York, New York
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


Top
 Profile  
Reply with quote  
 Post subject: Re: Native colors in moissanite?
PostPosted: Sun Apr 15, 2018 8:24 pm 
Offline
Platinum Member
User avatar

Joined: Fri Jun 25, 2010 10:06 pm
Posts: 2213
Location: Rochester, MN / Toronto, ON
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...).


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Gemology Style ported to phpBB3 by Christian Bullock