Mineral Factbook

Bytownite

Series / solid solution

Bytownite is a calcium-rich plagioclase feldspar. Compositions vary between the end-member species Anorthite and Albite.

Photos

Bytownite specimen photo
Animalculum · CC BY 4.0 · Commons
Bytownite specimen photo
Shannon Heinle · CC0 · Commons
Bytownite specimen photo
John Sobolewski (JSS) · CC BY 3.0 · Commons
Bytownite specimen photo
Dave Dyet http://www.shutterstone.com http://www.dyet.com · Public domain · Commons

About Anorthite (major)

Full reference data — crystallography, X-ray diffraction, and cited physical properties — is on the Anorthite species page.

FormulaCa(Al2Si2O8)
Hardness (Mohs)6-6.5
Specific gravity17
Density (calculated)2.797
Crystal systemtriclinic
Color rangegray, red, white
Streakred

About Albite (minor)

Full reference data — crystallography, X-ray diffraction, and cited physical properties — is on the Albite species page.

FormulaNa(AlSi3O8)
Hardness (Mohs)5.5
Specific gravity2.63-2.66
Density (calculated)2.621
Crystal systemtriclinic
Color rangered, white, yellow
Streakwhite