Arakiite

Formula: (Zn,Mn)(Mn,Mg)12(Fe,Al)2(AsO3)(AsO4)2(OH)23

Origin of name: Named for Dr. Takaharu Araki (1929-), University of Chicago, for his numerous crystal-structure contributions to the science of mineralogy.

 

Crystal system: Monoclinic

Crystal class: 

Twinning: 

Unit cell: a = 14.248 Å, b = 8.228 Å, c = 24.23 Å, β = 93.62°

 

Colour: Reddish brown, orange brown

Diaphaneity: Opaque to translucent

Luster: Resinous - metallic

Habit: Micaceous - Platy texture with "flexible" plates., Aggregates - Made of numerous individual crystals or clusters., Anhedral Grains - Granular minerals without the expression of crysta l shapes

Hardness: 3-4

Specific gravity: 3.4 (calculated)

Cleavage: Perfect [001]

Tenacity: Brittle, uneven

Streak: Pale brown

 

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