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FELDSPAR

Overview:The name "feldspar" comes from "field stone", because when feldspar weathers, it releases large amounts of

plant nutrients, such as potassium, which enrich the soil.

Feldspar minerals are aluminum silicates of either potassium,

sodium, and calcium. It is a group of minerals related to each other in structure and chemical composition

Feldspars are a family of minerals that include moonstone (adularia), amazonite, sunstone,

and labradorite. Feldspars also tend to crystallize in igneous enviroments, but are also present in many metamorphic rocks.

Physical Properties:

Feldspar

Feldspar Birthstone

Color
grey, pink, green and brown
Hardness
6-6.5
Specific Gravity
2.55-2.76
Refractive index
1.52-1.568

Usage:Feldspars helps one to let go of the old and embrace new exciting methods of reaching one's goals. It is a very useful industrial mineral that finds applications in making glass, plumbing fixtures, tile and pottery.

Type:

Orthoclase:Orthoclase feldspar is a potassium aluminium silicate. It includes the attractive but infrequently seen moonstone.

Sunstone:The premier U.S. gem-quality feldspar is the red labradorite, known as sunstone, mined in Oregon.

Moonstone:Moonstone is a variety of feldspar, and the shimmer which is called "schiller" or "adularescence", is caused by the intergrowth of two different types of feldspar, with different refractive indexes

Occurrence: Feldspar occurs in the United States, India, Russia.