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The geological definition of mineral normally excludes compounds that occur only in living beings. However, some minerals are often biogenic (such as calcite) or are organic compounds in the sense of chemistry (such as mellite). Moreover, living beings often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks.
In geology and mineralogy, a mineral group is a set of mineral species with essentially the same crystal structure and composed of chemically similar elements. [1] Silicon-oxygen double chain in the anions of amphibole minerals. For example, the amphibole group consists of 15 or more mineral species, most of them with the general unit formula A ...
The classification of minerals is a process of determining to which of several groups minerals belong based on their chemical characteristics. Since the 1950s, this classification has been carried out by the International Mineralogical Association, which classifies minerals into the following broad classes: Classification of non-silicate minerals
The basic level of definition is that of mineral species, each of which is distinguished from the others by unique chemical and physical properties. For example, quartz is defined by its formula, SiO 2, and a specific crystalline structure that distinguishes it from other minerals with the same chemical formula (termed polymorphs). When there ...
A rare-earth mineral contains one or more rare-earth elements as major metal constituents. Rare-earth minerals are usually found in association with alkaline to peralkaline igneous magmas in pegmatites or with carbonatite intrusives. Perovskite mineral phases are common hosts to rare-earth elements within the alkaline complexes.
In the context of nutrition, a mineral is a chemical element. Some "minerals" are essential for life, but most are not. [1] [2] [3] Minerals are one of the four groups of essential nutrients; the others are vitamins, essential fatty acids, and essential amino acids. [4] The five major minerals in the human body are calcium, phosphorus ...
Whitlockite is a member of the phosphate group of minerals with three distinct occurrences. For many years, these occurrences were thought to be identical. However, recent studies using x-ray and electron diffraction have been able to identify compositional differences that separate one type of whitlockite from another.
Similarly, the range of chemical composition allows chlorite group minerals to exist over a wide range of temperature and pressure conditions. For this reason chlorite minerals are ubiquitous minerals within low and medium temperature metamorphic rocks, some igneous rocks, hydrothermal rocks and deeply buried sediments.