why to brighten feldspar?

1.       What is Feldspar used for?

Orthoclase and Albite are more used for industrial process. In 2011,  20.7 million Tones of feldspar were produced, mostly by three countries: Turkey (5 Mt), Italy (4.7 Mt) and China (2.1 Mt)(USGS).

Feldspar is a common raw material used in glassmaking, ceramics, and to some extent as a filler and extender in paint, plastics, and rubber. Feldspar is ground to about 20 mesh for glassmaking and to 200 mesh or finer for most ceramic and filler applications.

About Feldspar I

1.      What is Feldspar?

The feldspars (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8 – BaAl2Si2O8) are a group of frame-like structure anhydrous aluminosilicate minerals, which are the most common mineral in the Earth, making up as much as 60% of the Earth's crust.

Generally speaking, there are three categories of feldspar: orthoclase (K-feldspar), plagioclase and celsian. Feldspar has two directions of cleavage that meet at close to a 90 degree angle. The included angle between two sets of cleavages of orthoclase is equal to 90 degrees, and less than 90 degrees for plagioclase.