Amesite

rutile

clinochlore

Formula: Mg2Al(AlSiO5)(OH)4
Phyllosilicate (sheet silicate), kaolinite - serpentine group
Specific gravity: 2.77 to 2.78
Hardness: 2½ to 3
Streak: White with very pale green tint
Colour: Originally pale greyish blue-green, also white, colourless, pale green, pink to lilac (chromian)
Environments

Metamorphic environments

Amesite is a product of low-grade metamorphism of rocks rich in aluminium and manganese (Webmin). It is found with clinochlore and magnetite, sometimes with grossular, diopside, calcite and clinozoisite, and occasionally with margarite; it occurs rarely as an alteration product of cancrinite (Dana).

At the Pensacola Mountains, Antarctica, amesite is associated with vesuvianite and chlorite (HOM).

At Black Lake, Canada, amesite is associated with grossular, calcite, diopside and clinozoisite (HOM).

At Mount Sobotka, lower Silesia, Poland, amesite occurs with a variety of chlorite in vesicles in rock fragments in the soils derived from a serpentinite (AM 76.647-652).

At the type locality, the Chester Emery Mines, Chester, Hampden county, Massachusetts, USA, amesite occurs in an emery deposit associated with rutile, magnetite, diaspore, clinochlore (Mindat, HOM) and chamosite (AM 29.422-430).

Back to Minerals