Chemical Formula: KMg3(AlSi3O10)(OH,F)2
Name Origin: From the Greek flogopos – “resembling fire.”Phlogopite is a yellow, greenish, or reddish-brown member of the mica family of phyllosilicates. It is also known as magnesium mica.Phlogopite is the magnesium endmember of the biotite solid solution series, with the chemical formula KMg3(AlSi3O10)(OH,F)2. Iron substitutes for magnesium in variable amounts leading to the more common biotite with higher iron content. For physical and optical identification, it shares most of the characteristic properties of biotite.
Name Origin: From the Greek flogopos – “resembling fire.”Phlogopite is a yellow, greenish, or reddish-brown member of the mica family of phyllosilicates. It is also known as magnesium mica.Phlogopite is the magnesium endmember of the biotite solid solution series, with the chemical formula KMg3(AlSi3O10)(OH,F)2. Iron substitutes for magnesium in variable amounts leading to the more common biotite with higher iron content. For physical and optical identification, it shares most of the characteristic properties of biotite.
History
Discovery date : 1841
Town of Origin: ANTWERP, NEW YORK
Country of Origin : USA
Optical properties
Optical and misc. Properties : Luminescent, fluorescent – Flexible – Elastique – Tenace – Transparent – Translucide – Macles possibles
Refractive Index : from 1,53 to 1,63
Axial angle 2V: 0-15°
Physical properties
Hardness : from 2,00 to 3,00
Density: from 2,78 to 2,85
Color : yellowish brown; brownish red; colorless; white; greenish; grey; brown yellow; blackish; whitish; green
Luster : submetallic; nacreous
Streak : white
Cleavage : Yes
Photos:
(OH,F)2 Name Origin: From the Greek flogopos - "resembling fire." Phlogopite is a yellow, greenish, or reddis){kind=link}