metamorphic
Gneiss
Gneiss
AI-generated identification · may be incorrectHardness of 6-7 on Mohs scale, foliated texture with distinct alternating light and dark compositional bands, vitreous to dull luster.
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 compositional bands, vitreous to dull luster.
Formation & geological history
Formed through high-temperature and high-pressure regional metamorphism of pre-existing igneous or sedimentary rocks deep within the Earth's crust.
Uses & applications
Used primarily as crushed stone for road construction, building facades, and dimensional stone tiles.
Geological facts
Some of the oldest known rocks on Earth, dating back over 4 billion years, are classified as gneiss.
Field identification & locations
Identify in the field by its characteristic zebra-like banding of light quartz/feldspar and dark biotite/amphibole minerals, commonly found in ancient shield areas.
More like this
