Quartz gravel/quartz is a familiar mineral and you can find them in many types of rocks. Pure quartz is transparent and consists of silicon dioxide with the chemical formula SiO2. Quartz has many important uses in science and industry. You can find quartz in many forms, and there are three main types of rocks: igneous, metamorphic, and sedimentary. Besides aluminum silicate, quartz is one of the most abundant materials in the rock composition of the earth’s continental crust. Quartz/quartz gravel is also one of the hardest minerals, the few minerals with significant hardness are beryl, spinel, topaz, sapphire and diamond. Erosion does not affect quartz as quickly as it does in most rock materials.
Frenchman Pierre Curie and his brother (Jacques) discovered quartz while examining a sample of sand in 1880 when they observed a strange phenomenon. When you subject quartz (silicon dioxide) to mechanical stress, you generate an electrical current. Conversely, when you subject quartz crystal to an electric field, it oscillates and vibrates at a specific frequency. This vibration and oscillation has a high regularity and accuracy. Known as “piezoelectric,” this phenomenon allowed researchers to create many sensitive devices. Among the most important are watches designed to measure time with high accuracy, since the quartz share in the watch industry has reached more than 85% of the global watch market.