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  2. Mineral (nutrient) - Wikipedia

    en.wikipedia.org/wiki/Mineral_(nutrient)

    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 ]

  3. Crystallography - Wikipedia

    en.wikipedia.org/wiki/Crystallography

    A crystalline solid: atomic resolution image of strontium titanate.Brighter spots are columns of strontium atoms and darker ones are titanium-oxygen columns. Octahedral and tetrahedral interstitial sites in a face centered cubic structure Kikuchi lines in an electron backscatter diffraction pattern of monocrystalline silicon, taken at 20 kV with a field-emission electron source

  4. Biomineralization - Wikipedia

    en.wikipedia.org/wiki/Biomineralization

    Fossil skeletal parts from extinct belemnite cephalopods of the Jurassic – these contain mineralized calcite and aragonite.. Biomineralization, also written biomineralisation, is the process by which living organisms produce minerals, [a] often resulting in hardened or stiffened mineralized tissues.

  5. Mineral - Wikipedia

    en.wikipedia.org/wiki/Mineral

    By definition, minerals have a characteristic atomic arrangement. Weakness in this crystalline structure causes planes of weakness, and the breakage of a mineral along such planes is termed cleavage. The quality of cleavage can be described based on how cleanly and easily the mineral breaks; common descriptors, in order of decreasing quality ...

  6. Magnesium - Wikipedia

    en.wikipedia.org/wiki/Magnesium

    Adding a cathodic poison captures atomic hydrogen within the structure of a metal. This prevents the formation of free hydrogen gas, an essential factor of corrosive chemical processes. The addition of about one in three hundred parts arsenic reduces the corrosion rate of magnesium in a salt solution by a factor of nearly ten.

  7. Mineralogy - Wikipedia

    en.wikipedia.org/wiki/Mineralogy

    Mineralogy applies principles of chemistry, geology, physics and materials science to the study of minerals. Mineralogy [n 1] is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts.

  8. Crystal structure - Wikipedia

    en.wikipedia.org/wiki/Crystal_structure

    The atomic packing factor is the proportion of space filled by these spheres which can be worked out by calculating the total volume of the spheres and dividing by the volume of the cell as follows: A P F = N p a r t i c l e V p a r t i c l e V unit cell {\displaystyle \mathrm {APF} ={\frac {N_{\mathrm {particle} }V_{\mathrm {particle} }}{V ...

  9. Biological roles of the elements - Wikipedia

    en.wikipedia.org/wiki/Biological_roles_of_the...

    Extremely rare on the Earth's surface (less than 1×10 −7 %, i.e. less than 1/10 as common as the least common essential element, selenium), thus has low potential for any kind of biological role. a: Toxic in some molecular forms. b: Radioactive. c: Has uses in medicine as a drug or implant.