（：Orthoclase), （KAlSi 3 O 8） [ 2 ], 。 ：SiO 2 （64.7%）、Al 2 O 3 （18.4%）、K 2 O（16.9%） [ 3 ]。,,。 [ 4 ] 、、,,,2.56, 6, 1290℃。 [ 5 ] ： （Sanidine） （Microcline）。 …
Orthoclase, common alkali feldspar mineral, a potassium aluminosilicate (KAlSi3O8); it usually occurs as variously coloured, frequently twinned crystals in granite. Orthoclase is used in the manufacture of glass and ceramics; occasionally, transparent crystals are cut as gems.
Orthoclase is frequently known as potassium feldspar or K-spar, and is easily distinguished from the plagioclase feldspars in hand sample by its lack of striations. In thin section, alkali feldspar grains often look like they're sprinkled with dirt (PPL) or tiny confetti (XPL).
Orthoclase, also known as K-spar and K-feldspar, is a common potassium feldspar mineral that crystallizes in the form of masses, small prismatic shards, elongated crystals, and thin plate-like layers. It can form on most granites and pegmatites, as well as being one of the main chemical components of Moonstone.
Orthoclase is a feldspar mineral with a chemical composition of KAlSi 3 O 8. It is one of the most abundant rock-forming minerals of the continental crust. Orthoclase is most widely known as the pink feldspar found in many granites and as the mineral assigned a hardness of "6" in the Mohs hardness scale .
Orthoclase is one of the most common minerals, and occurs in numerous mineral environments. It is polymorphous with the minerals Microcline and Sanidine . These three minerals form the Potassium Feldspar group .
Intrusive and extrusive igneous, and metamorphic rocks. Common world wide occurrences. Link to MinDat Location Data. From the Greek orthos - "right" and kalo -" I cleave" in allusion to the mineral's right angle of good cleavage. Comments: Striated, dark violet crystal of lorenzenite in cream-colored orthoclase.
An important rock-forming mineral, orthoclase is the potassium-bearing end member of the potassium sodium feldspar solid-solution series. It is a major component of granite its pink crystals give granite its typical color. Crystalline orthoclase can also be white, colorless, cream, pale yellow, or brownish red.
Orthoclase, or orthoclase feldspar (endmember formula K Al Si 3 O 8), is an important tectosilicate mineral which forms igneous rock. The name is from the Ancient Greek for "straight fracture", because its two cleavage planes are at right angles to each other.
