Kunzite info needed - Lee Little can you help?

[LD]

I've just started to learn about silver-smithing (although I need to say that this is using silver art clay that produces 99.9% silver so not the traditional route). Anyway, you can set gemstones into this medium before firing over a gas hob (or using a hand held torch).

What I want to know is ............. I have a 4ct pear shaped Kunzite that I love and want to make into a pendant (Lee your geometric silver pendants were my inspiration) BUT I don't know whether I can heat a Kunzite like this - ie direct over a flame. I've cooked one in an oven before but that has a slow ramp up heat and cool down. Obviously I wouldn't quench the piece and would let it cool naturally.

Does anybody know if I can do this with a Kunzite please?

 

[minousbijoux]

Not too long ago, Gene provided a "recipe" for heating some type of stone over an open flame. It might have been zircon (not that that helps in this situation), but it might also have been kunzite, I just don't remember.

 

[LD]

Not too long ago, Gene provided a "recipe" for heating some type of stone over an open flame. It might have been zircon (not that that helps in this situation), but it might also have been kunzite, I just don't remember.

Thanks Minou - my concern is that I have to put the silver over a direct flame (ie 0 degrees to hot within minutes and keep it on the flame for about 10 minutes or so) with the gemstone so that it's encompassed in the setting during the firing process. I would think the gemstones I can use will be limited. Interestingly, the instructions say you can use Tanzanite and Sapphire (and the information doesn't specify treated or untreated sapphires) but I'm highly doubtful about that!!! I certainly don't intend to chuck those in the flames!

 

[Lee Little]

Sorry I did not see this post earlier, actually only discovered it when searching my name on Google!
I would not expose Kunzite to any heat as it IS sensitive. Have you tried it yet?
Many gems are heat sensitive and will crack, pop or change color when heated. Clean Sapphires such as lab created are about as stable as it gets. I think Diamonds are good too. Inclusions and some treatments are not friendly with heat. I saw an entire thread on what stones can be used in silver clay but it was another forum. I don't use any clay but it looks fun.
Personally I trust very few stones to be heated. I generally remove and replace stones in a re-size. A bit off topic but also I never put ANY stone in an acid pickle except if I want to see if it will damage it or not. (one of my favorite test for leaded glass filled or not, of course, it will ruin a leaded glass gem).
Likely a Google search will provide many answers. I can also check my data bank on any particular stone if you have another in mind. Since I am posting on this thread they will send me email notices of any response so I will answer more promptly. Best regards, Lee

 

[LD]

Hi Lee - thanks for replying and you may like to know that unfortunately I did decide to experiment.

The upshot is that the pretty pink Kunzite turned into an opaque cracked awful looking stone! The only saving grace was that it was horribly windowed in the first place so this closed up the window

 

[Lee Little]

OH!! Well, no more unsightly window, that is positive, LOL.
Sometimes we just have to experiment, it is the best way to fully realize anything.
Have you made any further discoveries with this art? It looks interesting to me as things like dragons, horses etc can be made with detail which are impractical to attempt with the style of craftsmanship that I use and are generally reserved for wax carvers. Best regards, Lee

 

[Lady_Disdain]

LD - usually, only synthetics and some corundum are fired in place. Naturals have a tendency to crack: not only from internal fractures and inclusions but also because the metal clay compresses it as it sinters (it shrinks 10% when fired). It is usually best to set larger (aka, not melee sized) stones after the piece is ready> either make a bezel to hold the stone or fix some sterling silver prongs (there is a technique to secure sterling silver findings to metal clay).

Have you checked out any good metal clay books? There are some excellent ones out there. I know McCreigh has one and his books are always good. Revere might have one as well but I am not sure.