Name

Formula

SiO₂

Al₂O₃

K₂O

Na₂O

CaO

BaO

Specific Density

Hardness

Type

Color

Potassium
Feldspar
 

K₂O·Al₂O₃·6SiO₂

<70

>16

>9

<4

2.56

6

orthoclase

White, pink, milky white

Sodium Feldspar

Na₂O·Al₂O₃·6SiO₂

63-70

16-20

≤1

≥8

2.60

6

albite

White, blue, gray, no-color

Field

Application

Quality requirement

Glass and Glass making products

Feldspar as raw material of flat glass and kinds of glass make products, it can decrease the glass melting point, reduce the use of calcined soda. Sodium feldspar as raw material of glass fiber can improve the fiber quality and as substitute of pyrophillite.

Al₂O₃>18%
Fe₂O₃<0.6%
Na₂O+K₂O>10%

Ceramic industry

Feldspar as blank material in the production of ceramic, enamel, electrotechnical porcelain products (20-40% addition) and as raw material to glaze (20-70% addition)

Fe₂O₃<0.3-1.0%

Cement industry

As one of raw material to producing white cement

Chemical Processing

Crushed feldspar can be used as filling material to latex, painting,carbamic acid, acetic acid, propylene or like products.

As filler, bigger content of free quartz is preferred; as filler to cosmetic powder, 2-8um alkali feldspar is required.

Abrasives

Powdered feldspar can be used in abrasive industry.

Other fileds

wide applications are found in paper making, refractory product, machine manufacturing, painting, welding rod etc that feldpar is used as filler.