Zircon is one of the heaviest gemstones, which means that it will look smaller than other varieties of the same weight. Zircon jewelry should be stored carefully because although zircon is relatively hard, it can abrade and facets can chip. Dealers often wrap zircons in individual twists of paper so that they will not knock against each other in a parcel.
•Color is brown, red, yellow, green, blue, black, and colorless.
•Luster is adamantine.
•Transparency crystals are transparent to translucent.
•Crystal System tetragonal; 4/m 2/m 2/m
•Crystal Habits: dipyramidal and prismatic as discussed above.
•Cleavage indistinct in two directions, prismatic.
•Fracture is uneven
•Hardness is 7.5
•Specific Gravity is 4.6-4.7
•Streak white
•Associated Minerals albite, biotite, garnets, xenotime and monazite.
•Other Characteristics: is sometimes fluorescent and darker crystals may be radioactive due to impurities of rare earth elements. Also index of refraction is 1.92 - 2.01
•Notable Occurances Seiland, Norway; Pakistan; Russia; Bancroft and Sudbury, Ontario, Canada and New Jersey and Colorado, USA.
•Best Field Indicators are crystal habit, hardness, luster and density.
A very unique characteristic of zircon is birefringence, meaning that light splits into two rays as it passes through the stone. As a result, the back facets appear as double images.