What is Turquoise?
Turquoise stone is a hydrous basic phosphate of copper and aluminum which is formed as water trickles through a host stone for about 30 million years, gradually leaving a deposit. If the mix has more copper, the turquoise will be colored in the blue range; if more aluminum, in the green to white range. The addition of zinc yields a yellow-green color and hardens the stone even more. The yellow-green color has been found so far only in Carico Lake, Damali, and Orville Jack turquoise from Nevada. What is the “matrix” in turquoise? Other colors that appear in a turquoise stone come from the host stone that the turquoise formed in, and are called “matrix.” A black matrix is usually from iron pyrite; a gold-brown matrix from iron oxide, and a yellow to brown matrix from rhyolite. Matrix that is thin and evenly spaced over the surface of the stone is commonly known as “spider web” matrix. Spider web matrix usually enhances the collectibility and value of turquoise. How has turquoise been use
