Pigeonite

Formula: (Mg,Fe,Ca)(Mg,Fe)Si2O6

Origin of name: after locality Pigeon Point, Minnesota, USA

 

Crystal system: monoclinic

Crystal class: 2/m

Twinning: 

Unit cell: a = 9.706, b = 8.95, c = 5.246, β = 108.59°

 

Colour: Brown, light purplish brown, greenish brown, black

Diaphaneity: Translucent to nearly opaque

Luster: Vitreous to dull

Habit: Crystals short prismatic, small grains

Hardness: 6

Specific gravity: 3.30 to 3.46

Cleavage: 4; {110} good, {001}, {010} and {100} parting

Tenacity: Brittle, conchoidal fracture

Streak: Gray white

 

Synonyms/varieties:

 

Comments: also found in meteorites

 

Back to Alphabetical list Colour photos Optical properties/Thin sections SEM images TEM images vibrational spectra description IR spectra Raman spectra N-IR spectra F-IR spectra IES spectra