Curated category
Industrial minerals
- SandstoneThe journey of sandstone begins with the physical and chemical weathering of bedrock. Silicate sand grains form as rocks break down under the influence of…
- GneissA geologist in the Czech Republic holds a sample of orthogneiss that reveals its coarse-grained texture to the unaided eye.
- GraniteGranite is a coarse-grained intrusive igneous rock composed mostly of quartz, alkali feldspar, mica and plagioclase. The word granite comes from the Latin…
- LimestoneThe mineral calcite forms the backbone of limestone, appearing as a crystal structure that defines the rock's identity. In samples from the Carmel Formation…
- DiamondThe atoms in a diamond arrange themselves into a crystal structure called diamond cubic. Each carbon atom bonds to four nearest neighbors, forming tetrahedra…
- GypsumA hand can bend a crystal of gypsum under its own pressure. This physical trait defines the mineral on the Mohs scale as having a hardness value of 2.
- AsbestosArchaeologists have uncovered evidence of asbestos use stretching back 4,500 years to the Lake Juojärvi region in East Finland.
- KaoliniteThe chemical formula for kaolinite is Al2Si2O5(OH)4. This mineral belongs to the phyllosilicate group, meaning it forms in flat sheets.