Moissanite addenda

Hello All,

An important omission from my earlier post on polishing this
stuff is the reaction of the stone to heat. There is a quite
dramatic colour change effect. This takes place at fairly low
temperatures. It seems to start at about normal dopping
temperature as a light brown then changes to a quite brilliant
yellow colour, returning to the original colour upon cooling.

An alcohol lamp or cigarette lighter make for a quick cheap
tester as this seems to be a characteristic. Any soot easily
washes off.

Tony.
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@Anthony_Lloyd-Rees
http://www.opalsinthebag.com
ICQ# 15173706

Ooooh! Very good point Tony! I have heated them a number of
times and I would call the color of a hot moissanite a yellowish
green. Very pronounced! For those that don’t know how to look
for double refraction, this could be a pretty good test. I
retipped an old mounting to accept a synthetic moissanite a day
or two ago, but I didn’t find a any flux etching as I think that
you posted earlier. This is not the first time that I have
retipped one. I have never noted any flux etching. Your post
made me double check. What kind of flux were you using?

Bruce D. Holmgrain
Maryland’s first JA certified Master Bench Jeweler
http://www.goldwerx.com
manmountaindense@goldwerx.com

Hello Bruce, I didn’t put the flux on the stone. I am a coloured
stone cutter and received this job via a local diamond cutter.
The job was originally taken in as a 'diamond ring retipping’
when the damage occured and the stone was sent out for repair. I
assumed the damage was flux from the job description and 15x
inspection revealed identical rings and etching/fusing patterns
similar to those I have seen on flux damaged sapphires. The
little black dots however were new to me. Rather than research
and experiment I would suggest just keeping the stone clean when
heating. Maybe the C3 people could provide answers?

Tony

I have probably set fifty or so of these things. A good number
(1/3 - 1/2?) in platinum. Some of these designer settings have
even required the stones to be soldered in. So far no cracks. I
have managed to chip one and a client has managed to crush one.
C3 replaced the one that the client crushed. As I said before, I
haven’t seen flux etching. I surely haven’t seen these black
specks. Perhaps someone tried to retip platinum with the stone
in? I use batterns flux and sometimes boric acid to check
oxidation myself.

If I can think of it, I may call C3 tomorrow. 

Bruce D. Holmgrain
Maryland’s first JA certified Master Bench Jeweler
http://www.goldwerx.com
manmountaindense@goldwerx.com