Trigonite

Formula: Pb3Mn(AsO3)2(AsO2OH)

Origin of name: from Greek for triangle

 

Crystal system: monoclinic

Crystal class: m

Twinning:

Unit cell: 

 

Colour: yellow to brownish yellow to dark brown

Diaphaneity: translucent

Luster: vitreous to adamantine

Habit: crystals thick tabular, triangular outline, highly modified

Hardness: 2 to 3

Specific gravity: 6.1 to 7.1

Cleavage: 2; {010} perfect, {101}good

Tenacity: 

Streak: 

 

Synonyms/varieties:

 

Comments: 

 

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