Diamond Simulants

Cubic Zirconia
Cubic Zirconia (CZ) is the most commonly encountered diamond simulant. All commercial CZ is formed in laboratories however, it is also found in nature. In both its synthetic and natural forms, CZ is colorless but color can be introduced. A thermal pen tester can quickly and easily detect CZ.
Synthetic moissanite
Synthetic moissanite is a new diamond simulant to join the long list of products that imitate diamonds. Although moissanite is being marketed as a new unique, synthetic gemstone, some of its properties are close enough to those of diamonds to lead to confusion in the trade.
Natural moissanite was first identified in a meteorite crater at the beginning of the twentieth century however; most is produced synthetically as natural moissanite is very rare. Chemically, it is 'silicon carbide', also known as 'carborundum', which is widely used for abrasive purposes and for use in the electronics industry.
Synthetic moissanite is a diamond simulant like Cubic Zirconia however; it can be passed as a diamond by the widely used thermal pen testers because it has similar thermal characteristics to diamonds. However, it can be easily identified by other methods.