Diagnostic Features
Hardness : 2-2.5
Streak : White to none.
Luster : Nonmetallic
Specific Gravity : 2.8
Cleavage : Present in one direction.
Fracture : None
Other : Mineral separates into perfectly parallel sheets.
Identification Tips
1. Biotite, like the other types of mica, consist of seemingly endless, flexible, transparent sheets. Therefore, mica crystals are referred to as "books." You can separate the sheets easily with your fingernail
2. Biotite possesses a black to dark brown sheen and this distinguishes it from other common mica types. Light passing through a single thin sheet of biotite resembles light passing through a weak sunglass lens.
Photographed by Michael Amadeus Klimetz
Biotite
Single Crystal
Otter Lake
Quebec
CANADA
Photographed by Michael P. Klimetz
Photographed by Michael P. Klimetz
Photographed by Michael P. Klimetz
[Crystals in Calcite]
CANADA
Sterling Hill Mine
Ogdensburg
Sussex County
NEW JERSEY
Photographed by Michael P. Klimetz
Kero's [Tilcon] Quarry
Byram Township
Sussex County
NEW JERSEY
Photographed by Michael P. Klimetz
Kero's [Tilcon] Quarry
Byram Township
Sussex County
NEW JERSEY
Photographed by Michael P. Klimetz
Kero's [Tilcon] Quarry
Byram Township
Sussex County
NEW JERSEY
Photographed by Michael P. Klimetz
Kero's [Tilcon] Quarry
Byram Township
Sussex County
NEW JERSEY
Photographed by Michael P. Klimetz
Kero's [Tilcon] Quarry
Byram Township
Sussex County
NEW JERSEY
Photographed by Michael P. Klimetz
[With Sodalite]
Bancroft Area
Ontario
CANADA
Photographed by Michael P. Klimetz
[With Sodalite]
Bancroft Area
Ontario
CANADA
Photographed by Michael P. Klimetz
[With Sodalite]
Bancroft Area
Ontario
CANADA
Photographed by Michael P. Klimetz
[With Sodalite]
Bancroft Area
Ontario
CANADA
Photographed by Michael P. Klimetz
[With Sodalite]
Bancroft Area
Ontario
CANADA
Photographed by Michael P. Klimetz
[Crystal Plates in Pegmatite with Muscovite]
Julianna Pegmatite
DSS Piława Górna Quarry
Lower Silesia
POLAND
Photographed by Michael P. Klimetz
[Crystal Plates in Pegmatite with Muscovite]
Julianna Pegmatite
DSS Piława Górna Quarry
Lower Silesia
POLAND
Photographed by Michael P. Klimetz
[Crystal Plates in Pegmatite with Muscovite]
Julianna Pegmatite
DSS Piława Górna Quarry
Lower Silesia
POLAND
Photographed by Michael P. Klimetz
[Crystal Plates in Pegmatite with Muscovite]
Julianna Pegmatite
DSS Piława Górna Quarry
Lower Silesia
POLAND
Photographed by Michael P. Klimetz
[Crystal Plates with Quartz and Tourmaline]
Big Mine
Alstead
Cheshire County
NEW HAMPSHIRE
Photographed by Michael P. Klimetz
[Crystal Plates with Quartz and Tourmaline]
Big Mine
Alstead
Cheshire County
NEW HAMPSHIRE
Photographed by Michael P. Klimetz
[Glassy Black Crystal Plate]
Silver Crater Mine
Faraday Township
Bancroft District
Hastings County
Ontario
CANADA
Photographed by Michael P. Klimetz
[Glassy Black Crystal Plate]
Silver Crater Mine
Faraday Township
Bancroft District
Hastings County
Ontario
CANADA
Photographed by Michael P. Klimetz
[Glassy Black Crystal Plate]
Silver Crater Mine
Faraday Township
Bancroft District
Hastings County
Ontario
CANADA
