Marialite is a
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, silica (silicon dioxide, ) is usually cons ...
with a chemical formula of
[ if a pure endmember or with increasing meionite content.][ Marialite is a member of the scapolite group and a solid solution exists between marialite and ]meionite
Meionite is a tectosilicate belonging to the scapolite group with the formula Ca4Al6Si6O24CO3. Some samples may also contain a sulfate group. It was first discovered in 1801 on Mt Somma, Vesuvius, Italy. It was named by Rene Just Haüy after με ...
, the calcium endmember.[ It is a rare mineral usually used as a collector's stone.
]
Crystallography
Marialite has tetragonal crystallography and a 4/m crystal class. It has a 4 fold rotation with 90° mirror planes. Crystals are usually prismatic with prominent forms of prisms and dipyramids.[Johnsen, O. (2000) Photographic Guide to Minerals of the World. 439 p. Oxford University Press, Great Clarendon Street, Oxford]
Marialite belongs to a uniaxial negative optical class which means it has one circular section and a principal section shaped like an oblate sphenoid.
Discovery and occurrence
Marialite was first described in 1866 for an occurrence in the Phlegrean Volcanic complex, Campania
(man), it, Campana (woman)
, population_note =
, population_blank1_title =
, population_blank1 =
, demographics_type1 =
, demographics1_footnotes =
, demographics1_title1 =
, demographics1_info1 =
, demog ...
, Italy. It was named by German mineralogist Gerhard vom Rath
Gerhard vom Rath (20 August 1830 – 23 April 1888), was a German mineralogist, born at Duisburg in Prussia.
Biography
Rath was educated at Cologne, at Bonn University, and finally at Berlin, where he graduated Ph.D. in 1853. In 1856 he became ...
for his wife, Maria Rosa vom Rath.[
Marialite occurs in regional and contact metamorphism: marble, calcareous gneiss, granulite and greenschist. It also occurs in skarn, pegmatite and ]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 t ...
ly altered volcanic rocks.[ This means that Marialite is formed in high pressure and/or high temperature environments.
]
References
{{Reflist
Tectosilicates
Halide minerals
Tetragonal minerals
Minerals in space group 87
Sodium minerals
Aluminium minerals