Natural fused crystal 724g, Brazil

Crystal is a colorless variety of quartz (SiO2). It usually occurs in the form of crystals in a six-crystal system with a hardness of 6.5-7.5 on the Mohs scale. It is formed, like most silicates, by crystallization from magma. Crystal is a widely used stone in jewelry (mostly with inserts), in laser and radio technology, for the production of optical instruments and in the glass industry. It is popular as a collection stone.