Gneiss
| Colour | Gray, Pink |
|---|
What is Gneiss?
Gneiss is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. This rock is formed under pressures ranging from 2 to 15 kbar, sometimes even more, and temperatures over 300 °C (572 °F). Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct cleavage.
How to identify Gneiss
Gneiss in different forms
Stones often confused with Gneiss
Frequently asked questions
How hard is Gneiss?
Gneiss's hardness varies; see the property table above.
What colour is Gneiss?
Gneiss is typically gray, pink.