Anorthite is a compositional variety of plagioclase feldspar. For a topic outline on this subject see List of basic Japan topics. Plagioclase is a very important series of tectosilicate Minerals within the Feldspar family Feldspar is the name of a group of rock-forming Minerals which make up as much as 60% of the Earth 's crust. Plagioclase is an abundant mineral in the Earth's crust. A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 In Geology, a crust is the outermost solid shell of a planet or moon The formula of pure anorthite is CaAl₂Si₂O₈. Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 WikipediaNaming The Chemical compound silicon dioxide, also known as silica or silox (from the Latin " Silex " is an Oxide Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the

Contents 1 Mineralogy 2 Occurrence 3 Details 4 See also 5 References

Mineralogy

Anorthite is the calcium-rich endmember of the plagioclase solid solution, the other endmember being albite, NaAlSi₃O₈. Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 An endmember in Mineralogy is a Mineral that is at the extreme end of a mineral series in terms of purity A solid solution is a Solid - state Solution of one or more solutes in a Solvent. Albite is a plagioclase Feldspar Mineral. It is the sodium endmember of the Plagioclase Solid solution series Sodium (ˈsoʊdiəm is an element which has the symbol Na( Latin natrium, from Arabic natrun) atomic number 11 atomic mass 22 Anorthite also refers to plagioclase compositions with more than 90 molecular percent of the anorthite endmember. In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by

Occurrence

Anorthite is a rare compositional variety of plagioclase. It occurs in unusual igneous and metamorphic rocks on Earth. Igneous rocks (etymology from Latin ignis, fire are rocks formed by solidification of cooled Magma (molten rock Metamorphism can be defined as the solid state recrystallisation of pre-existing rocks due to changes in heat and/or pressure and/or introduction of fluids i Its type localities are Monte Somma and Valle di Fassa, Italy. In some natural sciences type locality (Latin locus typicus) is the typical or representative location and is typically the first example of a newly discovered or described Mount Vesuvius (in Italian Monte Vesuvio and in Latin Mons Vesuvius) is an active Stratovolcano east of Naples Italy (Italia officially the Italian Republic, (Repubblica Italiana is located on the Italian Peninsula in Southern Europe, and on the two largest

It also makes up much of the lunar highlands. Anorthite was discovered in samples from comet Wild 2, and the mineral is an important constituent of Ca-Al-rich inclusions in rare varieties of chondritic meteorites. A comet is a small Solar System body that orbits the Sun and when close enough to the Sun exhibits a visible coma (atmosphere or a tail — Comet 81P/Wild, also known as Wild 2, is a Comet named after Swiss astronomer Paul Wild (pronounced Vilt) who discovered it in 1978 A calcium-aluminium-rich inclusion or Ca-Al-rich inclusion (CAI is a Centimeter -sized light-colored Calcium - and Aluminium -rich inclusion Chondrites are stony Meteorites that have not been modified due to Melting or Differentiation of the parent body

Details

Crystallographic system	Triclinic
Colours	Normally colourless or white, colourless in thin section. In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal. In Crystallography, the triclinic Crystal system is one of the 7 lattice Point groups A crystal system is described by three basis vectors
Lustre	Vitreous
Hardness	6-6. Lustre (or luster) is a description of the way light interacts with the surface of a Crystal, rock, or Mineral. The Mohs scale of mineral hardness characterizes the scratch resistance of various Minerals through the ability of a harder material to scratch a softer material 5
Refractive index	1. The refractive index (or index of Refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves is reduced inside the medium 51
Cleavage	3: 1 perfect, 1 good, 1 poor
Twinning	A variety of types are present, including multiple lamellar and Carlsbad twins
Pleochroism	None

See also

• Feldspars
• List of minerals
• In-Situ Resource Utilization

References

• WebMineral entry

Cleavage, in Mineralogy, is the tendency of crystalline materials to split along definite planes creating smooth surfaces of which there are several named types Crystal twinning occurs when two separate crystals share some of the same Crystal lattice points in a symmetrical manner Pleochroism is an Optical phenomenon in which grains of a rock appear to be different colors when observed at different angles under a Petrographic microscope. Feldspar is the name of a group of rock-forming Minerals which make up as much as 60% of the Earth 's crust. This is a List of Minerals for which there are Wikipedia articles In Space exploration, In-Situ Resource Utilization (ISRU describes the proposed use of resources found or manufactured on other planetary bodies (the Moon Mars etc

© 2009 citizendia.org; parts available under the terms of GNU Free Documentation License, from http://en.wikipedia.org
Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic