Moissanite

Moissanite is silicon carbide, written chemically as SiC. Synthetic moissanite is used as a jewellery gemstone and can resemble diamond. It is a different material from both natural and laboratory grown diamond, despite a potentially similar appearance.

GIA documented in 1997 that ordinary thermal diamond probes available at that time could identify synthetic moissanite as diamond. A positive reading from a simple thermal conductivity tester is therefore not sufficient evidence by itself. The instrument must be capable of distinguishing the materials concerned.

When buying or selling, specify the material, testing method and any professional report precisely. Terms such as genuine stone or diamond like do little to establish identity. A gemmologist should examine uncertain stones before they are priced or advertised as diamonds.