Axinite-(Mn)

minerals

rhodonite

chamosite

johannsenite

4Mn2+2Al4[B2Si8O30](OH)2
Sorosilicates (Si2O7 groups), axinite group
Specific gravity: 3.30 to 3.36
Hardness: 6½ to 7
Streak: White
Colour: Brown, golden-yellow
Solubility: Insoluble in water, hydrochloric, nitric and sulphuric acid
Common impurities: Ti,Fe,Mg,Na,K,H2O
Environments:

Pegmatites
Metamorphic environments
Hydrothermal environments

Axinite-(Mn) is found in quartz - calcite veins, igneous contact zones especially with mafic rocks and some granite pegmatites (Dana). It is typically formed by contact metamorphism and boron contact metasomatism (HOM).
Associated minerals include quartz, plagioclase, microcline, chamosite, spessartine, andradite, johannsenite, rhodonite, tourmaline, chlorite, K-feldspar and datolite (Dana, HOM).

Localities

In Minnesota, axinite-(Mn) has been found in a pegmatite vein cutting metamorphosed iron formation at a contact with gabbro (HOM).

At the type locality the Franklin Mine, Franklin Mining District, Sussex County, New Jersey, USA, axinite-(Mn) occurs in a zinc-iron polymetalic metamorphosed deposit hosted by marble. Associated minerals include rhodonite, hendricksite, hancockite, baryte and andradite (Mindat).

Back to Minerals