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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 ]
Amethyst crystals – a purple quartz Apophyllite crystals sitting right beside a cluster of peachy bowtie stilbite Aquamarine variety of beryl with tourmaline on orthoclase Arsenopyrite from Hidalgo del Parral, Chihuahua, Mexico Aurichalcite needles spraying out within a protected pocket lined by bladed calcite crystals Austinite from the Ojuela Mine, Mapimí, Durango, Mexico Ametrine ...
The 'IMA database of mineral properties' (rruff.info/ima) has 173 species with 'not an IMA approved mineral' tag, some are an intermediate member of a solid solution series, others are "recently" discredited minerals. [4] I – intermediate member of a solid-solution series. H – hypothetical mineral (synthetic, anthropogenic, etc.)
Phosphate minerals are minerals that contain the tetrahedrally coordinated phosphate (PO 3− 4) anion, sometimes with arsenate (AsO 3− 4) and vanadate (VO 3− 4) substitutions, along with chloride (Cl −), fluoride (F −), and hydroxide (OH −) anions, that also fit into the crystal structure.
Mineral classification schemes and their definitions are evolving to match recent advances in mineral science. Recent changes have included the addition of an organic class, in both the new Dana and the Strunz classification schemes. [152] [153] The organic class includes a very rare group of minerals with hydrocarbons. The IMA Commission on ...
Pyrolusite is a mineral consisting essentially of manganese dioxide (Mn O 2) and is important as an ore of manganese. [7] It is a black, amorphous appearing mineral, often with a granular, fibrous, or columnar structure, sometimes forming reniform crusts. It has a metallic luster, a black or bluish-black streak, and readily soils the fingers.
Bertrandite is a beryllium sorosilicate hydroxide mineral with composition: Be 4 Si 2 O 7 (OH) 2. Bertrandite is a colorless to pale yellow orthorhombic mineral with a hardness of 6–7. It is commonly found in beryllium rich pegmatites and is in part an alteration of beryl. Bertrandite often occurs as a pseudomorphic replacement of beryl.
The name mineralocorticoid derives from early observations that these hormones were involved in the retention of sodium, a mineral.The primary endogenous mineralocorticoid is aldosterone, although a number of other endogenous hormones (including progesterone [1] and deoxycorticosterone) have mineralocorticoid function.