Augelite is an aluminium
phosphate mineral
Phosphate minerals contain the tetrahedrally coordinated phosphate (PO43−) anion along sometimes with arsenate (AsO43−) and vanadate (VO43−) substitutions, and chloride (Cl−), fluoride (F−), and hydroxide (OH−) anions that also fit ...
with formula:
Al2(
P O4)(O
H)
3. The shade varies from colorless to white, yellow or rose. Its
crystal system
In crystallography, a crystal system is a set of point groups (a group of geometric symmetries with at least one fixed point). A lattice system is a set of Bravais lattices. Space groups are classified into crystal systems according to their poin ...
is
monoclinic
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic s ...
.
[Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, and Abraham Rosenzweig: "Dana's new mineralogy", p. 851. John Wiley & Sons, 1997]
It was first described by
Christian Wilhelm Blomstrand for an occurrence in
Västanå iron mine at
Scania
Scania, also known by its native name of Skåne (, ), is the southernmost of the historical provinces (''landskap'') of Sweden. Located in the south tip of the geographical region of Götaland, the province is roughly conterminous with Skåne ...
,
Sweden in 1868 and derives its name from the
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
αύγή in reference to its pearly
lustre.
[
It occurs as a product of ]metamorphism
Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of ch ...
of phosphate
In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid .
The phosphate or orthophosphate ion is derived from phosph ...
bearing peraluminous sediments and in high-temperature hydrothermal
Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with th ...
ore deposit
Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit.Encyclopædia Britannica. "Ore". Encyclopædia Britannica Online. Retrieved 7 April ...
s. It occurs in association with attakolite, svanbergite
Svanbergite is a colorless, yellow or reddish mineral with the chemical formula Sr Al3( P O4)( SO4)(O H)6. It has rhombohedral crystals.Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, and Abraham Rosenzweig: " Dana's new ...
, lazulite
Lazulite () is a blue, phosphate mineral containing magnesium, iron, and aluminium phosphate. Lazulite forms one endmember of a solid solution series with the darker iron rich scorzalite.
Lazulite crystallizes in the monoclinic system. Crystal ...
, hematite, trolleite, berlinite
Berlinite ( aluminium phosphate, chemical formula AlPO4 or Al(PO4)) is a rare high-temperature hydrothermal or metasomatic phosphate mineral. It has the same crystal structure as quartz with a low temperature polytype isostructural with α–quar ...
, rutile
Rutile is an oxide mineral composed of titanium dioxide (TiO2), the most common natural form of TiO2. Rarer polymorphs of TiO2 are known, including anatase, akaogiite, and brookite.
Rutile has one of the highest refractive indices at visib ...
, pyrophyllite
Pyrophyllite is a phyllosilicate mineral composed of aluminium silicate hydroxide: Al2Si4O10(OH)2. It occurs in two forms (habits): crystalline folia and compact masses; distinct crystals are not known.
The folia have a pronounced pearly luste ...
, baryte, arsenopyrite
Arsenopyrite ( IMA symbol: Apy) is an iron arsenic sulfide (FeAsS). It is a hard ( Mohs 5.5-6) metallic, opaque, steel grey to silver white mineral with a relatively high specific gravity of 6.1. When dissolved in nitric acid, it releases elem ...
, stannite, pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrite's metallic luster and pale brass-yellow hue giv ...
, andorite, cassiterite and zinkenite
Zinkenite is a steel-gray metallic sulfosalt mineral composed of lead antimony sulfide Pb9 Sb22 S42. Zinkenite occurs as acicular needle-like crystals.
It was first described in 1826 for an occurrence in the Harz Mountains, Saxony-Anhalt, Germa ...
.[
]
References
Phosphate minerals
Monoclinic minerals
Minerals in space group 12
{{Phosphate-mineral-stub