zir·co·ni·um | ˈzər-ˌkän
A common mineral occurring in small crystals which is heated, cut, and polished to form a brilliant blue-white gemstone
Zircon is used as a refractory when opaque and as a gemstone when transparent.
Zircon is not a man-made stone like Cubic Zirconium is.
Although it is frequently color-treated, Zircon occur naturally in clear, yellow, orange, brown, and red.
Zircon is the chief source of zirconium.