noun
- Plural of oligoclase; a type of feldspar mineral that is a sodium-rich plagioclase, typically white or grayish in color and found in igneous rocks.
Usage: technical; mineralogy
Examples
- Oligoclases are commonly found in granitic rocks and other igneous formations.
- The geologist identified several oligoclases in the thin section of the rock sample.
- Oligoclases belong to the plagioclase feldspar group and contain sodium and aluminum silicates.
- The white crystals in the granite specimen were determined to be oligoclases through X-ray diffraction.