"chathum diffusion"?

[Arkteia]

Browsing ebay, I stumbled across a "nice veryunique stone" (spessartine). It was described as treated by "chathum diffusion". (I keep their original spelling

). I tried to google "chatham diffusion"; apparently there is such a term and it refers to treatment of many stones, not only sapphires and rubies although I could not get any specifics. I sent a question to the seller; got a totally unintellible answer. The stone was listed as IF; the whole situation made me automatically wary of any "IF" or even "VVS" colored stones. As of today, all I know is that CZ is sometimes colored and sold as garnets. Does anyone know about garnet enhancements? Also, ebay is full of cheaper stones such as chrome diopsides which I never saw before; bought a pair, they look stunning. But I heard from someone that chrome diopsided above 2cts are included; most of the stones listed on ebay are "VVS". Is it safe to buy anything there?

 

[chrono]

I believe the spessartine to be a synthetic stone. Chatham is well known for producing lab grown sapphires, rubies and other gemstones. It is the diffusion part that has me stumped though. Diffusion usually refers to a dye treatment of the stone. Natural garnets are not enhanced but it is very possible that this stone is a dyed synthetic stone from the sound of the treatment. There are honest gemstone vendors on eBay but those are few and rare.

ETA
More research yield that it refers to being a lab grown stone that is also diffused (dyed).

 

[T L]

Date: 11/3/2009 2:15:59 PM
Author:crasru
Browsing ebay, I stumbled across a ''nice veryunique stone'' (spessartine). It was described as treated by ''chathum diffusion''. (I keep their original spelling

). I tried to google ''chatham diffusion''; apparently there is such a term and it refers to treatment of many stones, not only sapphires and rubies although I could not get any specifics. I sent a question to the seller; got a totally unintellible answer. The stone was listed as IF; the whole situation made me automatically wary of any ''IF'' or even ''VVS'' colored stones. As of today, all I know is that CZ is sometimes colored and sold as garnets. Does anyone know about garnet enhancements? Also, ebay is full of cheaper stones such as chrome diopsides which I never saw before; bought a pair, they look stunning. But I heard from someone that chrome diopsided above 2cts are included; most of the stones listed on ebay are ''VVS''. Is it safe to buy anything there?

This really is a small part of the whole problem with ebay. I would say that most colored stone vendors are like sharks, and you have to watch out for them, and be very careful what you buy off of ebay. Obtaining trusted vendor lists is part of what ebayers do in order to find good deals on colored gems. Therefore, to answer your question, is it safe to buy anything from ebay? Yes, but I would proceed with caution. There are some trusted ebay vendors. Here''s a recent thread on them. I would not trust that "chatham diffused" stone as a natural colored stone.

https://www.pricescope.com/community/threads/tell-us-the-ebay-gem-sellers-youve-had-good-experiences-with.127886/

 

[Lady_Disdain]

Date: 11/3/2009 2:15:59 PM
Author:crasru
[Browsing ebay, I stumbled across a ''nice veryunique stone'' (spessartine). [...] Is it safe to buy anything there?

Hi Crasru!

Yes, it can be safe to buy in ebay - I do it quite often. However, you must take a few precautions:

- Buy from trusted vendors. The ones I trust the most are cutters and dealers whom I know already and who also sell on ebay. For example: Dan Stair, Mastercutgems (Dana) and GemLine (Michael). The alternative is to throughly check out the seller: toolhaus.org, the good folk at PS, etc

- If it is too good to be true, it probably isn''t. I have snagged some huge bargains, mostly from trusted sellers who put up a stone that was, for some reason overlooked by everyone else. Very, very few vendors will try to auction off a perfect pad starting at $1. If he does, then check past auctions for the prices. If the seller is consistently selling at too low prices, then something is wrong (ocasionally is perfectly alright: sometimes a lucky person snags an overlooked bargain).

- Check for a good return policy. If everything is OK, then it is useless. If you get a dud, at least you can return and only be out shipping.