Zircon is a type of gemstone. It's desirable because of the range of colors that it comes in and because it's less expensive than other gemstones, especially diamonds. Although it sometimes gets confused with cubic zirconia, the two are only similar in name.
Zircon is a zirconium silicate and is considered a neosilicate. Neosilicates are minerals that contain silicon and oxygen. Other gemstones that are considered neosilicates include garnets, peridot, topaz, andalusite, kyanite, tanzanite and quartz. A heat treatment alters the color of zircon. This treatment is usually completed at the mine site prior to cutting the stone. Using varying temperatures and by applying heat for a few hours, the brownish color of the zircon turns a permanent yellow, blue or colorless (white) shade.
White zircon is often times confused with cubic zirconia. Cubic zirconia is lab created material, while white zircon is a natural mineral, with a completely different chemistry. Cubic zirconia is made from zirconium dioxide in its crystallized form.
Zircon is found in a number of places around the world. In Asia, white zircon is mined in Cambodia, Vietnam, Thailand, Burma and Sri Lanka. In Africa, it can be found in Tanzania, Madagascar, Mozambique and Nigeria, with these sources becoming more important because of the increased business in the heavy mining industry and ability to export it. The gemstone can also be found in Brazil and Australia.
White zircon was once used as a diamond substitute, because it was inexpensive. White zircon was even sold under the name “Matura Diamond,” so called because of its source location. But because of its brittleness, white zircon jewelry should be stored is a safe spot, as it can wear along facet edges and be broken easily. Because of this brittleness, white zircon is less resilient than a diamond.
Zircon has a high refractive index. A refractive index is the measure of the bending of a ray of light when passing from one medium into another. Colorless, or white, zircon has a 1.810 to 2.024 refractive index and has the ability to split white light into spectral colors. Jewelers cut zircon in a specific way to prevent the interior from looking fuzzy because of the facet image doubling. The cutter needs to orient the table of the stone to the optic axis. Therefore, colorless stones are brilliant cut.