Muscovite vs. Biotite — What's the Difference?

A potassium aluminum silicate mineral, KAl2(AlSi3O10)(OH)2, the most common form of mica, which ranges from colorless or pale yellow to gray and brown, has a pearly luster, and is used as an insulator. Also called white mica.

Biotite is a common group of phyllosilicate minerals within the mica group, with the approximate chemical formula K(Mg,Fe)3AlSi3O10(F,OH)2. It is primarily a solid-solution series between the iron-endmember annite, and the magnesium-endmember phlogopite; more aluminous end-members include siderophyllite and eastonite.

Muscovite (also known as common mica, isinglass, or potash mica) is a hydrated phyllosilicate mineral of aluminium and potassium with formula KAl2(AlSi3O10)(F,OH)2, or (KF)2(Al2O3)3(SiO2)6(H2O). It has a highly perfect basal cleavage yielding remarkably thin laminae (sheets) which are often highly elastic.

A dark-brown or dark-green to black mica, K(Mg,Fe)3(Al,Fe)Si3O10(OH)2, found in igneous and metamorphic rocks.

A native or resident of Moscow or Muscovy.

(mineral) A dark brown mica; it is a mixed aluminosilicate and fluoride of potassium, magnesium and iron.

Of or relating to Moscow, Muscovy, or the Muscovites.

Mica containing iron and magnesia, generally of a black or dark green color; - a common constituent of crystalline rocks. See Mica.

(mineral) A pale brown mineral of the mica group, being a basic potassium aluminosilicate with the chemical formula KAl₂(Si₃Al)O₁₀(OH,F)₂; used as an electrical insulator etc.

Dark brown to black mica found in igneous and metamorphic rock

A native or inhabitant of Muscovy or ancient Russia; hence, a Russian.

An inhabitant of Moscow.

Common potash mica, essentially KAl3Si3O10(OH)2. It is used as an electrical insulator. See Mica.

A colorless or pale brown mica with potassium

A resident of Moscow

Of or relating to the residents of Moscow;