perthitic — adjective see perthite * * * perthitic / itˈik/ adjective • • • Main Entry: ↑perthite … Useful english dictionary
perthitic — adjective Of, pertaining to, or resembling perthite … Wiktionary
perthitic — per·thit·ic … English syllables
perthite — perthitic /peuhr thit ik/, adj. perthitically, adv. /perr thuyt/, n. Mineral a variety of feldspar containing irregular bands of albite in microcline. [1832; named after Perth, Ontario, Canada; see ITE1] * * * any member of a class of… … Universalium
Myrmekite — describes a vermicular, or wormy, intergrowth of quartz in plagioclase. The intergrowths are microscopic in scale, typically with maximum dimensions less than 1 millimeter. The plagioclase is sodium rich, usually albite or oligoclase. These… … Wikipedia
feldspar — /feld spahr , fel /, n. any of a group of minerals, principally aluminosilicates of potassium, sodium, and calcium, characterized by two cleavages at nearly right angles: one of the most important constituents of igneous rocks. Also, felspar.… … Universalium
Feldspar — is the name of a group of rock forming minerals which make up as much as 60% of the Earth s crust.Feldspar. [http://www.ima na.org/about industrial minerals/feldspar.asp What is Feldspar?] Industrial Minerals Association. Retrieved on July 18… … Wikipedia
Pegmatite — is a very coarse grained igneous rock that has a grain size of 20 mm or more; such rocks are referred to as pegmatitic .Most pegmatites are composed of quartz, feldspar and mica; in essence a granite . Rarer intermediate and mafic pegmatite… … Wikipedia
Napoleonite — Napoleonite, also called corsite because the stone is found in the island of Corsica, is a variety of diorite which is characterized by orbicular structure. The grey matrix of the stone has the normal appearance of a diorite, but contains many… … Wikipedia
List of rock textures — This page is intended to be a list of rock textural and morphological terms. A * Adcumulate * Agglomeritic * Adamantine a type of lustre * Amygdaloidal * Anhedral * Antitaxial veins * Aphanitic * Aplitic; aplite * Augen textured gneiss *… … Wikipedia