Moissanite

Moissanite is silicon carbide (SiC), a carbide mineral exceedingly rare in nature and first identified in a meteorite, today produced almost entirely as a synthetic gem. Natural moissanite is one of the rarest minerals on Earth. It was first discovered in 1893 by Henri Moissan in fragments of the Canyon Diablo meteorite in Arizona. For over a century, all known natural moissanite was either meteoritic or found as microscopic inclusions in kimberlite pipes and other mantle-derived rocks. Natural gem-quality moissanite essentially doesn't exist.

All moissanite sold as a gemstone is laboratory-grown silicon carbide. Charles & Colvard developed the first commercial gem-quality moissanite in the late 1990s using a thermal growing process. The resulting crystals are optically superior to diamond in some respects: moissanite has higher refractive index (2.65 vs diamond's 2.42) and significantly more fire/dispersion (0.104 vs 0.044). It literally sparkles more than diamond.

Moissanite has disrupted the engagement ring market by offering diamond-like appearance, superior optical properties, and ethical sourcing at roughly 10% of diamond's price. It's the hardest substance commercially available after diamond (9.25 Mohs), making it genuinely practical for daily wear.

Moissanite is identified by its extreme brilliance and fire (noticeably more than diamond), hardness of 9.25 (second only to diamond), and double refraction (visible doubling of back facet edges when viewed through the table with a loupe). Diamond is singly refractive.

Distinguish from diamond (singly refractive, less fire, higher thermal conductivity), cubic zirconia (lower hardness at 8.5, no double refraction, higher density), and white sapphire (much less fire and brilliance). Most jewelers use electronic diamond testers - older thermal testers read moissanite as diamond; newer multi-testers can distinguish them.