What minerals are in plagioclase feldspar?
What minerals are in plagioclase feldspar?
What is Plagioclase? Plagioclase is the name of a group of feldspar minerals that form a solid solution series ranging from pure albite, Na(AlSi3O8), to pure anorthite, Ca(Al2Si2O8). Minerals in this series are a homogenous mixture of albite and anorthite.
What type of mineral is feldspar?
feldspar, any of a group of aluminosilicate minerals that contain calcium, sodium, or potassium. Feldspars make up more than half of Earth’s crust, and professional literature about them constitutes a large percentage of the literature of mineralogy.
What is plagioclase feldspar structure?
Plagioclase is a series of tectosilicate (framework silicate) minerals within the feldspar group….
| Plagioclase | |
|---|---|
| Category | Feldspar mineral group, tectosilicate |
| Formula (repeating unit) | NaAlSi3O8 – CaAl2Si2O8 |
| Crystal system | Triclinic |
| Crystal class | Pinacoidal (1) (same H-M symbol) |
What is plagioclase mineral?
Plagioclase is a member of the feldspar group (like orthoclase) and is a framework silicate. Plagioclase consists of a solid solution between the albite and anorthite end-members, and together with quartz is the most common of the rock forming minerals.
What Colour is plagioclase feldspar?
white
Plagioclase feldspar is identified by its non-metallic, vitreous to pearly luster; white to dark gray color; and two good cleavages at nearly 90o. Plagioclase feldspar has striations on some cleavage surfaces. Its hardness is 6. Its specific gravity is 2.6 to 2.8.
What is the importance of feldspar?
Feldspars are used as fluxing agents to form a glassy phase at low temperatures and as a source of alkalies and alumina in glazes. They improve the strength, toughness, and durability of the ceramic body, and cement the crystalline phase of other ingredients, softening, melting and wetting other batch constituents.
What’s feldspar used for?
Feldspars are used widely in the glass and ceramics industries. Alkali feldspars are more commonly used commercially than plagioclase feldspars. Albite, or soda spar as it is known commercially, is used in ceramics.
What properties does diorite have?
Diorite is a coarse-grained intrusive igneous rock. It contains large interlocking, randomly oriented crystals. It is a dark coloured rock, usually medium to dark grey, containing many mafic crystals. Mostly it looks like dark coloured granite.
Where is diorite used?
It is used as a base material in the construction of roads, buildings, and parking areas. It is also used as a drainage stone and for erosion control. In the dimension stone industry, diorite is often cut into facing stone, tile, ashlars, blocking, pavers, curbing, and a variety of dimension stone products.
How is plagioclase feldspar used?
Plagioclase is used in the manufacture of glass and ceramics; the iridescent varieties peristerite and labradorite are valued as gemstones or ornamental material. The primary importance of plagioclase, however, derives from its role in rock formation.
Where is plagioclase found?
igneous rocks
Plagioclase is found in almost all igneous rocks and most metamorphic rocks, but is less common in sedimentary rocks where it usually weathers to clay minerals or a fine grained variant of muscovite (sericite).