http://webmineral.com/data/Biotite.shtml WebSpecific gravity: 3 to 3.05 common (3.03-3.07) Cleavage: two directions good, fibrous, brittle, the compact variety is tough Refractive index: 1.619-1.644 ... and a little potassium FELDSPAR. Hornblende (see AMPHIBOLE) and biotite (see MICA) may constitute about 20 percent of the rock, with small amounts of other accessory minerals ...
Amphibole Group Minerals Properties and …
WebSpecific Gravity: 2.9 to 3.5 (varies depending upon composition) Diagnostic Properties: Cleavage, color, elongate habit: Chemical Composition ... Hornblende is easly confused with biotite. Distiguishing … WebSpecific Gravity, etc. Luster Mineral Name 6 to 6.5 Gray to greenish-black Conchoidal fracture Brassy yellow, high specific gravity Metallic Pyrite 6 Black to dark ... Vitreous Biotite Mica 4 White 4 cleavage planes Colorless, yellow, white, blue, green, or violet, transparent to translucent Vitreous Fluorite nothing shall ever tear us asunder in greek
DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY
WebBiotite is found in igneous and metamorphic rocks. It has a Mohs hardness of 2 to 4 and a specific gravity of 2.8 to 3.3. Biotite is non-magnetic and has a low electrical conductivity. What Is The Chemical Composition Of Biotite? The chemical formula of biotite is K(Fe,Mg)_3AlSi_3O_10(F,OH)_2. Biotite is a potassium-rich mica mineral. WebThe specific gravity values of amphiboles range from about 2.9 to 3.6. Amphiboles yield water when heated in a closed tube and fuse with difficulty in a flame. ... The amphiboles typically occur with plagioclase feldspar, … WebBiotite, another common mica, is recognized by the IMA as a mineral group of related micas rather then as an individual mineral type. Phlogopite is one of the member minerals of the Biotite group, and is chemically and structurally similar to the other Biotite minerals. ... Specific Gravity: 2.8 - 2.9: Luster: Pearly: Cleavage: 1,1: Fracture ... nothing shall be impossible scripture