Zircon

Zircon (pronounced /ˈzɜrkən/; including hyacinth or yellow zircon) is a mineral belonging to the group of nesosilicates. Its chemical name is zirconium silicate and its corresponding chemical formula is ZrSiO₄. A common empirical formula showing some of the range of substitution in zircon is (Zr_1-y, REE_y)(SiO₄)_1-x(OH)_4x-y. Zircon forms in silicate melts with concentrated incompatible elements and accepts high field strength elements into its structure. For example, hafnium is almost always present in quantities ranging from 1 to 4. The crystal structure of zircon is tetragonalcrystal system. The natural color of zircon varies between colorless, yellow-golden, red, brown, blue, and green. Colorless specimens that show gem quality are a popular substitute for diamond; these specimens are also known as "Matura diamond".