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The mineral pyrite (/ ˈ p aɪ r aɪ t / PY-ryte), [6] or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S 2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral .
[12] [13] The six-line form has been classified as a mineral by the IMA in 1973 [14] with the nominal chemical formula 5 Fe 2 O 3 ·9 H 2 O. [15] Other proposed formulas are Fe 5 HO 8 ·4 H 2 O [16] and Fe 2 O 3 ·2 FeO(OH) ·2.6 H 2 O. [17] However, its formula is fundamentally indeterminate as its water content is variable.
Permineralization is a process of fossilization of bones and tissues in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. Because of the nature of the casts, permineralization is particularly useful in studies of the internal structures of organisms, usually of ...
In this way, given certain conditions (which are largely temperature-dependent) kerogens will break down to form hydrocarbons through a chemical process known as cracking, or catagenesis. A kinetic model based on experimental data can capture most of the essential transformation in diagenesis, [ 10 ] and a mathematical model in a compacting ...
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.
The group is named for its most common member, pyrite (fool's gold), which is sometimes explicitly distinguished from the group's other members as iron pyrite. Pyrrhotite (magnetic pyrite) is magnetic, and is composed of iron and sulfur , but it has a different structure and is not in the pyrite group.
Mineral alteration refers to the various natural processes that alter a mineral's chemical composition or crystallography. [1]Mineral alteration is essentially governed by the laws of thermodynamics related to energy conservation, relevant to environmental conditions, often in presence of catalysts, the most common and influential being water (H 2 O).
Most minerals on Earth formed after photosynthesis by cyanobacteria (pictured) began adding oxygen to the atmosphere. Mineral evolution is a recent hypothesis that provides historical context to mineralogy. It postulates that mineralogy on planets and moons becomes increasingly complex as a result of changes in the physical, chemical and ...