4008 x 4784 px | 33,9 x 40,5 cm | 13,4 x 15,9 inches | 300dpi
Aufnahmedatum:
3. Februar 2014
Weitere Informationen:
Smokey alligator quartz (elestial quartz) is quartz with natural terminations all over the faces and body of a layered or etched crystal. It is a silicon dioxide crystal with a hardness of 7 and with a hexagonal crystal. This sample is from Capalinha Minas Gerais, Brazil. Quartz is the second most abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz, several of which are semi-precious gemstones. Especially in Europe and the Middle East, varieties of quartz have been since antiquity the most commonly used minerals in the making of jewelry and hardstone carvings.