Larnite is a

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 ...

silicate mineral Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust. In mineralogy, the crystalline forms of silica (silicon dio ...

with the formula . It is the calcium member of the olivine group of minerals. It was first described from an occurrence at Scawt Hill,

Larne Larne (, , the name of a Gaelic Ireland, Gaelic territory)Larne/Latharna
Placenames Database of Ireland. is a to ...

Northern Ireland Northern Ireland ( ; ) is a Countries of the United Kingdom, part of the United Kingdom in the north-east of the island of Ireland. It has been #Descriptions, variously described as a country, province or region. Northern Ireland shares Repub ...

in 1929 by Cecil Edgar Tilley and named for the location. At the type locality it occurs with

wollastonite Wollastonite is a calcium Silicate minerals, inosilicate mineral (calcium, Casilicon, Sioxygen, O3) that may contain small amounts of iron, magnesium, and manganese substituting for calcium. It is usually white. It forms when impure limestone or D ...

spurrite Spurrite is a white, yellow or light blue mineral with monoclinic crystals. Its chemical formula is Ca5( Si O4)2 CO3. Spurrite is generally formed in contact metamorphism zones as mafic magmas are intruded into carbonate rocks.Smith, J.V. (196 ...

perovskite Perovskite (pronunciation: ) is a calcium titanium oxide mineral composed of calcium titanate (chemical formula ). Its name is also applied to the class of compounds which have the same type of crystal structure as , known as the perovskite (stru ...

, merwinite,

melilite Melilite refers to a mineral of the melilite group. Minerals of the group are solid solutions of several endmembers, the most important of which are gehlenite and åkermanite. A generalized formula for common melilite is ( Ca, Na)2( Al, Mg ...

and gehlenite. It occurs in contact metamorphosed

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

s and

chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Ch ...

s adjacent to

basaltic Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron ( mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% ...

intrusives.

Dicalcium silicate Calcium silicate can refer to several silicates of calcium including: *CaO·SiO2, wollastonite (CaSiO3) *2CaO·SiO2, larnite (Ca2SiO4) *3CaO·SiO2, alite or (Ca3SiO5) *3CaO·2SiO2, (Ca3Si2O7). This article focuses on Ca2SiO4, also known as calc ...

is chemically β–, sometimes represented by the idealized oxide formula also noted in the

cement chemist notation Cement chemist notation (CCN) was developed to simplify the formulas cement chemists use on a daily basis. It is a shorthand way of writing the chemical formula of oxides of calcium, silicon, and various metals. Abbreviations of oxides The main ...

(CCN). When used in the cement industry, the mineral is usually referred to as

belite Belite is an industrial mineral important in Portland cement manufacture. Its main constituent is dicalcium silicate, Ca2SiO4, sometimes formulated as 2 CaO · SiO2, SiO2 (C2S in cement chemist notation). Etymology The name was given by Alfred E ...

References

* Nesosilicates Monoclinic minerals Minerals in space group 14 {{silicate-mineral-stub