metamorphic
Gneiss
Gneiss
AI-generated identification · may be incorrectHardness of 6-7 on Mohs scale, foliated texture with distinct alternating light and dark bands, vitreous to dull luster, specific gravity of 2.6-2.9.
Identified More metamorphic →
Explore Gneiss in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 6-7 on Mohs scale, foliated texture with distinct alternating light and dark bands, vitreous to dull luster, specific gravity of 2.6-2.9.
Formation & geological history
Formed through high-grade regional metamorphism of preexisting igneous or sedimentary rocks under intense heat and pressure.
Uses & applications
Used primarily as crushed stone for road construction, building facades, landscaping, and dimensional stone.
Geological facts
Some gneiss specimens date back over 4 billion years, representing some of the oldest surviving rock fragments on Earth.
Field identification & locations
Identify in the field by characteristic compositional banding (gneissic banding). Found worldwide in ancient shields and core mountain ranges.
More like this
