Xanthoxenite is a rare

calcium Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...

iron(III) In chemistry, iron(III) or ''ferric'' refers to the element iron in its +3 oxidation state. ''Ferric chloride'' is an alternative name for iron(III) chloride (). The adjective ''ferrous'' is used instead for iron(II) salts, containing the catio ...

phosphate mineral Phosphate minerals are minerals that contain the tetrahedrally coordinated phosphate () anion, sometimes with arsenate () and vanadate () substitutions, along with chloride (Cl−), fluoride (F−), and hydroxide (OH−) anions, that also fit in ...

with formula: Ca₄Fe³⁺₂(PO₄)₄(OH)₂·3H₂O. It occurs as earthy pale to brownish yellow incrustations and lath shaped crystals. It crystallizes in the

triclinic crystal system class=skin-invert-image, 180px, Triclinic (a ≠ b ≠ c ≠ a and α, β, γ, 90° pairwise different) In crystallography, the triclinic (or anorthic) crystal system is one of the seven crystal systems. A crystal system is described by three b ...

. It occurs as an alteration product of

triphylite Triphylite is a lithium iron(II) phosphate mineral with the chemical formula LiFePO4.IMA-CNMNC List of Mine ...

pegmatite A pegmatite is an igneous rock showing a very coarse texture, with large interlocking crystals usually greater in size than and sometimes greater than . Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic c ...

s. It occurs associated with

apatite Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of Hydroxide, OH−, Fluoride, F− and Chloride, Cl− ion, respectively, in the crystal. The formula of the admixture of ...

whitlockite Whitlockite is a mineral, an unusual form of calcium phosphate. Its formula is Ca9(Mg Fe)(PO4)6PO3O H. It is a relatively rare mineral but is found in granitic pegmatites, phosphate rock deposits, guano caves and in chondrite meteorites. It was f ...

childrenite Childrenite is a rare hydrated phosphate mineral with elements iron, manganese, aluminium, phosphorus, oxygen and hydrogen. Its chemical formula is and it has a molecular weight of 229.83 g/mol. Its specific gravity is 3.2 and it has a Mohs hard ...

–

eosphorite Eosphorite is a brown (occasionally pink) manganese hydrous phosphate mineral with chemical formula: Mn Al( P O4)(O H)2· H2O. It is used as a gemstone. Eosphorite crystallizes in the monoclinic crystal system. It forms slender prismatic crysta ...

, laueite,

strunzite Strunzite (Mn2+Fe3+2(PO4)2(OH)26H2O) is a light yellow mineral of the strunzite group, first discovered in 1957. It crystallizes in the triclinic system and has a light, vitreous luster, a specific gravity of 2.52 and a Mohs hardness of 4. Asso ...

, stewartite, mitridatite,

amblygonite Amblygonite () is a fluorophosphate mineral, , composed of lithium, sodium, aluminium, phosphate, fluoride and hydroxide. The mineral occurs in pegmatite deposits and is easily mistaken for albite and other feldspars. Its density, cleavage and fl ...

and

siderite Siderite is a mineral composed of iron(II) carbonate (FeCO3). Its name comes from the Ancient Greek word (), meaning "iron". A valuable iron ore, it consists of 48% iron and lacks sulfur and phosphorus. Zinc, magnesium, and manganese commonly ...

. It has been found in

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

Ukraine Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the nor ...

, and the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. It was first described in 1920 for an occurrence in North Groton,

Grafton County, New Hampshire Grafton County is a County (United States), county in the U.S. state of New Hampshire. As of the 2020 United States census, 2020 census, the population was 91,118. Its county seat is the town of Haverhill, New Hampshire, Haverhill. In 1972, the ...

References

Phosphate minerals Triclinic minerals Minerals in space group 2 {{Phosphate-mineral-stub