Axinite

Real mineral · uncommon · Ca₂(Fe,Mn)Al₂BSi₄O₁₅(OH)

A complex calcium iron manganese boron silicate forming wedge-shaped crystals in skarns and metamorphic contact zones. Displays strong pleochroism, appearing brown, violet, or yellow depending on viewing direction.

Identity

Formula
Ca₂(Fe,Mn)Al₂BSi₄O₁₅(OH)
Chemical class
silicate
Also known as
Ferro-axinite (iron-rich), Tinzenite (manganese-rich)

Crystallography

Crystal system
triclinic
Habits
tabular, wedge-shaped, massive
Fracture
conchoidal

Physical properties

Mohs hardness
7
Density
3.31 g/cm³
Luster
vitreous
Colors
brown, violet-brown, gray, yellow, green
Streak
white
Transparency
transparent, translucent

Geology

Origins
metamorphic, hydrothermal
Host rocks
skarn, granite, limestone
Associated minerals
Grossular, Diopside, Epidote, Calcite
Geography
France, Russia, Mexico, USA, Australia

Classification

Rarity
uncommon
Gem quality
Yes

Arcane properties

Affinity
earth, arcane
Effects
warding, elemental earth
Planar origin
Material Plane

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