Mineral | Types & Uses | Britannica
2024年8月25日 · Mineral, naturally occurring homogeneous solid with a definite chemical composition and a highly ordered atomic arrangement. Usually formed by inorganic processes, there are several thousand known mineral species, about 100 of which constitute the major mineral components of rocks.
Mineral - Classification, Properties, Types | Britannica
2024年8月25日 · Mineral - Classification, Properties, Types: Since the middle of the 19th century, minerals have been classified on the basis of their chemical composition. Under this scheme, they are divided into classes according to their dominant anion or …
Mineral - Occurrence, Formation, Compound | Britannica
2024年8月25日 · Minerals form in all geologic environments and thus under a wide range of chemical and physical conditions, such as varying temperature and pressure. The four main categories of mineral formation are: (1) igneous, or magmatic, in which minerals crystallize from a melt, (2) sedimentary, in which minerals are the result of sedimentation, a ...
Obsidian | Rock, Color, Composition, & Uses | Britannica
obsidian, igneous rock occurring as a natural glass formed by the rapid cooling of viscous lava from volcanoes. Obsidian is extremely rich in silica (about 65 to 80 percent), is low in water, and has a chemical composition similar to rhyolite. Obsidian has a glassy lustre and is slightly harder than window glass.
Silica mineral | Uses, Properties & Structure | Britannica
Silica mineral, any of the forms of silicon dioxide (SiO2), including quartz, tridymite, cristobalite, coesite, stishovite, lechatelierite, and chalcedony. Various kinds of silica minerals have been produced synthetically; one is keatite. Silica minerals make up approximately 26 percent of …
mineral - Kids | Britannica Kids | Homework Help
Minerals are inorganic substances, meaning that they do not come from an animal or a plant. Mineralogy is the science of minerals. Mineralogists, or people who study minerals, have identified hundreds of minerals. Some of the most common minerals are metals—for example, gold, silver, copper, and platinum. Diamond, quartz, sulfur, mica, talc ...
Cobalt | Uses, Properties, & Facts | Britannica
4 天之前 · It is found in small quantities in terrestrial and meteoritic native nickel-iron, in the Sun and stellar atmospheres, and in combination with other elements in natural waters, in ferromanganese crusts deep in the oceans, in soils, in plants and animals, and in minerals such as cobaltite, linnaeite, skutterudite, smaltite, heterogenite, and ...
Mineral oil | Uses, Benefits, Properties | Britannica
mineral oil, a clear, colourless, oily liquid that is a by-product of the distillation of petroleum. Mineral oil is used in medicine as a laxative and as an emollient. Given orally, it coats the bowel and softens the stool mass, thus easing the latter’s passage.
Mining | Definition, History, Examples, Types, Effects, & Facts ...
2024年10月10日 · mining, process of extracting useful minerals from the surface of the Earth, including the seas. A mineral, with a few exceptions, is an inorganic substance occurring in nature that has a definite chemical composition and distinctive physical properties or molecular structure.
Mineral - Hardness, Mohs Scale, Crystalline | Britannica
2024年8月25日 · Mineral - Hardness, Mohs Scale, Crystalline: Hardness (H) is the resistance of a mineral to scratching. It is a property by which minerals may be described relative to a standard scale of 10 minerals known as the Mohs scale of hardness.