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Related to Saussurite: gabbro


A white or grayish, tough, compact mineral aggregate composed chiefly of a mixture of albite or oligoclase and zoisite or epidote.



(named after H. B. Saussure), a fine-grained aggregate of the minerals zoisite and albite, sometimes also containing calcite and sericite impurities or, less often, chlorite. Saussurite is produced by the alteration of plagioclases containing a small amount of anorthite. Particles range in size from thousandths to hundredths of a millimeter and can be distinguished only under a microscope. Most commonly, saussurite replaces plagioclases having an andesine-labradorite composition. It is formed during the metamorphosis of rocks, and is encountered most frequently in gabbros, diabases, and dolerites. The process by which plagioclases are replaced by saussurite is called saussuritization.

References in periodicals archive ?
Groundmass is ne grained with felsophyric composition exhibits alteration to sericite, epidote, carbonates, kaolinite and saussurite etc.
Subhedral plagioclase is slightly to extensively altered to saussurite and sericite.