"Oligoclase" is a word in ENGLISH

A mineral of the feldspar family, triclinic in crystallization, and in composition a silicate of alumina and soda. It is …

A kind of triclinic feldspar found in the Andes.

An eruptive rock allied to trachyte, consisting essentially of a triclinic feldspar, with pyroxene, hornblende, or hypersthene.

A mineral occurring in triclinic crystals approaching pyroxene in angle, and of a greenish black color. It is a silicate …

A rock of igneous origin, consisting of augite and triclinic feldspar, with grains of magnetic or titanic iron, and also …

A basic, dark-colored, holocrystalline, igneous rock, consisting essentially of a triclinic feldspar and pyroxene with magnetic iron; -- often limited …

An igneous, crystalline in structure, consisting essentially of a triclinic feldspar and hornblende. It includes part of what was called …

A dark-colored, basic, igneous rock, composed essentially of pyroxene and a triclinic feldspar with magnetic iron. By many authors it …

A mineral of the feldspar group, like orthoclase or common feldspar in composition, but triclinic in form.

A granular crystalline rock consisting essentially of a triclinic feldspar (as labradorite) and hypersthene.

A general term used of any triclinic feldspar. See the Note under Feldspar.

Triclinic.

Having, or characterized by, three unequal axes intersecting at oblique angles. See the Note under crystallization.