What is the cleavage of orthoclase?
| Orthoclase | |
|---|---|
| Twinning | Typically displays Carlsbad twinning. Baveno and manebach twins have also been reported in orthoclase. |
| Cleavage | Has perfect cleavage on {001} and good cleavage on {010}. Cleavages intersect at 90°. It can be difficult to see cleavage in thin section due to orthoclase’s low relief. |
| Fracture | Uneven |
What is KAlSi3O8 called?
Orthoclase Mineral Data
| General Orthoclase Information | |
|---|---|
| Chemical Formula: | KAlSi3O8 |
| Name Pronunciation: | Orthoclase + Pronunciation |
| Synonym: | Adularia |
| Orthose |
What type of mineral is orthoclase?
feldspar group
Orthoclase is a member of the feldspar group (like plagioclase) and is a framework silicate. Orthoclase, also known as alkali feldspar or K-feldspar, is one end-member of a solid solution between orthoclase and albite.
What is the difference between plagioclase feldspar and orthoclase feldspar?
Note that the plagioclase differs from the orthoclase in terms of the additional metals, plagioclase having calcium or sodium and orthoclase having potassium. The feldspars have similar physical properties and typically have a luster ranging from glassy to pearly.
What is the difference between potassium feldspar and plagioclase feldspar?
The feldspars are divided into two main groups: Potassium feldspar (“K-spar”) and plagioclase (“plag”). Both display two cleavages and an overlapping range of colors, but only plagioclase displays tiny grooves on one cleavage known as striations.
What does Adularia mean?
Definition of adularia : a transparent or translucent orthoclase.
What is Carlsbad twinning?
A twinned crystal in which the twinning axis is the c axis, the operation is a rotation of 180 degrees, and the contact surface is parallel to the side pinacoid. It is quite common in the alkali feldspars. An alternative spelling is Karlsbad twin. Carlsbad twin of feldspar.
What are the main uses of feldspar?
Feldspar is a common raw material used in glassmaking, ceramics, and to some extent as a filler and extender in paint, plastics, and rubber. In glassmaking, alumina from feldspar improves product hardness, durability, and resistance to chemical corrosion.
Is feldspar a rock or mineral?
Feldspar is the name of a large group of rock-forming silicate minerals that make up over 50% of Earth’s crust. [1] They are found in igneous, metamorphic, and sedimentary rocks in all parts of the world. Feldspar minerals have very similar structures, chemical compositions, and physical properties.
What is orthoclase used for?
Orthoclase is used in the manufacture of glass and ceramics; occasionally, transparent crystals are cut as gems. Orthoclase is primarily important as a rock-forming mineral, however, and is abundant in alkali and acidic igneous rocks, in pegmatites, and in gneisses.