Definitions for PERTHITE
perthite

WiktionaryRate this definition:0.0 / 0 votes

1. perthitenoun

   A laminated mixture of two feldspars of different colours

WikipediaRate this definition:0.0 / 0 votes

1. Perthite

   Perthite is used to describe an intergrowth of two feldspars: a host grain of potassium-rich alkali feldspar (near K-feldspar, KAlSi3O8, in composition) includes exsolved lamellae or irregular intergrowths of sodic alkali feldspar (near albite, NaAlSi3O8, in composition). Typically, the host grain is orthoclase or microcline, and the lamellae are albite. If sodic feldspar is the dominant phase, the result is an antiperthite and where the feldspars are in roughly equal proportions the result is a mesoperthite.The intergrowth forms by exsolution due to cooling of a grain of alkali feldspar with a composition intermediate between K-feldspar and albite. There is complete solid solution between albite and K-feldspar at temperatures near 700 °C and pressures like those within the crust of the Earth, but a miscibility gap is present at lower temperatures. If an alkali feldspar grain with an intermediate composition cools slowly enough, K-rich and more Na-rich feldspar domains separate from one another. In the presence of water, the process occurs quickly. When megascopically developed, the texture may consist of distinct pink and white lamellae representing exsolved white albite (NaAlSi3O8) in pink microcline. The intergrowths in perthite have a great variety of shapes. If cooling is sufficiently slow, the alkali feldspar may exsolve to form separate grains with near-endmember albite and K-feldspar compositions. The largest documented single crystal of perthite was found in Hugo Mine in South Dakota and measured about 10.7 m (35 ft) x 4.6 m (15 ft) x 1.8 m (5 ft 11 in).The gem varieties of potassium feldspar, amazonite and moonstone are variant colored perthites.

Webster DictionaryRate this definition:0.0 / 0 votes

1. Perthitenoun

   a kind of feldspar consisting of a laminated intertexture of albite and orthoclase, usually of different colors

2. Etymology: [So called from Perth, in canada.]

WikidataRate this definition:0.0 / 0 votes

1. Perthite

   Perthite is used to describe an intergrowth of two feldspars: a host grain of potassium-rich alkali feldspar includes exsolved lamellae or irregular intergrowths of sodic alkali feldspar. Typically the host grain is orthoclase or microcline, and the lamellae are albite. If sodic feldspar is the dominant phase, the result is an antiperthite. The intergrowth forms by exsolution due to cooling of a grain of alkali feldspar with a composition intermediate between K-feldspar and albite. There is complete solid solution between albite and K-feldspar at temperatures near 700 °C and pressures like those within the crust of the Earth, but a miscibility gap is present at lower temperatures. If an alkali feldspar grain with an intermediate composition cools slowly enough, K-rich and more Na-rich feldspar domains separate from one another. In the presence of water, the process occurs quickly. When megascopically developed, the texture may consist of distinct pink and white lamellae representing exsolved white albite in pink microcline K-feldspar. The intergrowths in perthite have a great variety of shapes. If cooling is sufficiently slow, the alkali feldspar may exsolve to form separate grains with near-endmember albite and K-feldspar compositions. The largest documented single crystal of perthite was found in Hugo Mine, South Dakota, US and measured ~10.7m x 4.6m x 1.8m. The gem varieties of potassium feldspar, amazonite and moonstone are variant colored perthites.

Anagrams for PERTHITE »

1. tephrite

How to pronounce PERTHITE?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

   US English

   Oliver

   British

   Wendy

   British

   Fred

   US English

   Tessa

   South African

How to say PERTHITE in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of PERTHITE in Chaldean Numerology is: 7

2. Pythagorean Numerology

   The numerical value of PERTHITE in Pythagorean Numerology is: 2

References

1. ^ Wiktionary
   https://en.wiktionary.org/wiki/Perthite
2. ^ Wikipedia
   https://en.wikipedia.org/wiki/Perthite
3. ^ Webster Dictionary
   https://www.merriam-webster.com/dictionary/PERTHITE
4. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=PERTHITE