02 Tsavorite: When Garnet is Green
The gemstone discoveries in East Africa in the 1960s transformed the jewelry world: new varieties, new colors, and new variations on existing species made that decade the most exciting time in the gemstone industry in our lifetimes.
The chain of discoveries was breathtaking: raspberry-red rhodolite garnet, a rainbow of fancy sapphire, rich red ruby, grass-green chrome tourmaline, the sunset hues of malaya garnet, and velvety-blue tanzanite. The grand finale was the discovery in 1968 in Tanzania of a magnificent brilliant green grossular garnet. The beautiful green garnet was also discovered on the Kenya side of the border in 1971, in the Taita Taveta district. In 1974, the new gem was named "Tsavorite," after the famous Tsavo National Park game preserve in Kenya by Tiffany & Co in New York, who introduced the gemstone to the world market.
Tsavorite has a beautiful vivid green color, is bright and lively with a high refractive index, and has a garnet's durability and high clarity.
Tsavorite comes from the East African bush: all the mines currently producing are in an arid grassy area with bare dry hills that runs across the border from Kenya to Tanzania. This area is home to snakes and an occasional lion.
Hundreds of millions of years ago, this land was covered by the ocean. Layers of organic sediment were deposited, eventually forming shale. Then the land was subjected to intense heat and pressure, folding and uplift, metamorphically changing the ocean floor into new minerals. This twisting and torturing of the rocks gave birth to the unusual gemstones of East Africa, many colored by the vanadium which is plentiful in these rocks because of their organic history in the ocean floor.
0 komentar:
Post a Comment