Moissanite is regarded as a diamond alternative, with some  optical properties exceeding those of diamond. It is marketed as a lower price  alternative to diamond. As some of its properties are quite similar to diamond,  testing equipment based on measuring thermal conductivity in particular may give  deceiving results. On the Mohs scale of mineral hardness moissanite is rated as  9.5, with diamond being 10. Because of its hardness, it can be used in  high-pressure experiments, as a replacement for diamond Products Details: Gem Weight(ct): 0.3 x 5pcs Gem Shape: Round Gem Type: Moissanite Gem Color: Diamond White Gem Size: 4.0mm/0.3ct x 5pcs Metal: 925 Sterling Silver Plating Color: White gold