Some Archaeological Gemstones

In ancient times the Chinese buried jade with their dead in the belief that the stone would prevent decomposition of the corpse. During the Han Dynasty (third century b.c.e. - third century c.e.), for example, pieces of jade were placed in each of the body orifices to ward off decay. It is ironic, therefore, that in contact with the corpse jade decayed and its hard, polished surface became damaged by chalky blemishes (Gaines and Handy 1975). 

Jadeite Mostly green, but also white and red Silicate of aluminum and sodium 3.3-3.5 6.5-7 

Nephrite Yellow, brown, green, blue, red, lavender Silicate of calcium, magnesium and iron 2.9-3.Z 6 -6.5 

Ruby and Sapphire. Ruby and sapphire are sister stones both are gemstone forms of fhe mineral corundum (composed of aluminum oxide). Pure corundum is colorless, buf a variety of frace elemenfs cause corundum to exhibif differenf colors. Ruby is red corundum, while sapphire is corundum in all colors excepf red. The red in rubies is caused by frace amounfs of chromium fhe more intense the red color of a ruby, fhe more chromium it contains. The blue in sapphires is caused by titanium and/or iron impurities (Garland 2002 Hughes 1997). 

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