The gemstone moissanite is very rare and belongs to the minerals. It is also known as silicon carbide and has the chemical composition SiC. Silicon carbide is formed at very high temperatures, for example in the Earth's mantle or when meteorites hit the Earth, generating a temperature of 1900 to 2000 °C. In its pure state, moissanite is colourless. The following rule applies: the smaller the moissanite, the less colourful it is. However, traces of other elements such as boron, aluminium or even nitrogen can cause it to take on a wide range of colours. Moissanite is mainly found in various meteorites, but it is also mined in volcanoes or diamond mines. The gemstone is one of the hardest naturally occurring substances with a Mohs hardness of 9.5 and is only surpassed in hardness by diamonds. As the mineral is so rare, it is usually produced synthetically in the laboratory from silicon dioxide and carbon and processed into jewellery. Its name goes back to the French scientist Henri Moissan, who determined the components of the mineral in 1904. Small, colourless moissanites in particular are very similar to diamonds, but are significantly more affordable due to their synthetic production.