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Naturally occurring gemstone quality Zincite is extremely rare. In fact the world's major source of highest quality gemstone material was the Tarnowskie Góry Zinc smelter in Poland's Upper Silesia mining district. The Zincite was formed when a smelter chimney sprang a leak, allowing an excess of oxygen to mix with the fumes inside the smelter. The oxygen that came in through the crack combined with the zinc to form zinc oxide (Zincite). The Zincite was then deposited in air vents, from which it was later found and collected when the chimney was knocked down during renovations. Apparently this particular leak introduced oxygen in almost perfect proportions to produce the most extraordinarily beautiful crystals of Zincite, and subsequent attempts to duplicate the process have not been successful. This Polish material was available in the 1980s and 90s at the Tucson gem show but it appears all the available supply has been depleted.
The optical properties of Zincite are exceptional with a refractive index over 2.0 (second only to diamond) and medium to strong dispersion. However it is relatively soft with a Mohs hardness of only 4.0, so cutting and setting is challenging to say the least. Fortunately the gem DW purchased had already been cut into an absolutely gorgeous red gemstone by Gerry Newman. We were not sure if we would be able to find anybody willing to set such a soft stone, but the price was right, and it was so beautiful DW decided to go ahead with the purchase just so she could have it in her collection.
Ideally, if we were going to set such a soft stone it would have been best as a pendant. However DW already has a lovely red ruby pendant so she much preferred to have it set as a ring. She knew there was no way this could be an every day ring, but thought a protective diamond halo would allow it to be worn as a "going out to dinner on a Saturday night" type of ring.
We have done a number of projects with DKJ and have learned to trust their judgement. We discussed with Amy if setting such a soft stone might be possible, and let her know we understood there was risk involved and the risk would be ours. She agreed to talk it over with her most skillful setter and get back to us. A couple of days later we heard the project was a go! Here are a few photos of DW's new Zincite ring set in 18ct yellow gold.
The 10.18ct stone faces up at 11.5x10.2, almost identical to DW's 5.05ct OEC. The difference explained by the specific gravity of Zincite being 60% higher than diamond, and this stone has a really high crown. DW's idea was with the OEC on her left hand, the Zincite would work well, and look great on her right hand. She was absolutely right, and It does seem the two rings are already becoming friends.
The optical properties of Zincite are exceptional with a refractive index over 2.0 (second only to diamond) and medium to strong dispersion. However it is relatively soft with a Mohs hardness of only 4.0, so cutting and setting is challenging to say the least. Fortunately the gem DW purchased had already been cut into an absolutely gorgeous red gemstone by Gerry Newman. We were not sure if we would be able to find anybody willing to set such a soft stone, but the price was right, and it was so beautiful DW decided to go ahead with the purchase just so she could have it in her collection.
Ideally, if we were going to set such a soft stone it would have been best as a pendant. However DW already has a lovely red ruby pendant so she much preferred to have it set as a ring. She knew there was no way this could be an every day ring, but thought a protective diamond halo would allow it to be worn as a "going out to dinner on a Saturday night" type of ring.
We have done a number of projects with DKJ and have learned to trust their judgement. We discussed with Amy if setting such a soft stone might be possible, and let her know we understood there was risk involved and the risk would be ours. She agreed to talk it over with her most skillful setter and get back to us. A couple of days later we heard the project was a go! Here are a few photos of DW's new Zincite ring set in 18ct yellow gold.
The 10.18ct stone faces up at 11.5x10.2, almost identical to DW's 5.05ct OEC. The difference explained by the specific gravity of Zincite being 60% higher than diamond, and this stone has a really high crown. DW's idea was with the OEC on her left hand, the Zincite would work well, and look great on her right hand. She was absolutely right, and It does seem the two rings are already becoming friends.
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