GEDRITE (Mg,Fe)5Al2(Si3Al011)2(OH)2. Orthorhombic

Description: Gedrite is a member of the amphibole group. It forms during medium to high grade regional metamorphism of ultramafic, iron-rich or clay-rich protoliths.

JACKSON COUNTY: Gedrite has been reported intergrown with cummingtonite in the iron formation of the Jackson County Iron Mine, SE Sect. 15 T.21N. R.3W. (Kimball, 1979).

OCONTO COUNTY: Gedrite occurs as tiny grains in metavolcanic rocks near Mountain. (Sims et. al., 1991).

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