Greywacke
A variety of Sedimentary
What is Greywacke?
Greywacke is a hard, dark-colored variety of sandstone sometimes used as a filler in construction. Taking on a subdued but attractive look when cut or polished, greywacke is sometimes used for flooring, decorative tiles, or flagstones. It may also be used in roads or seawalls.
Uses & Applications
Greywacke is very hard, making it a prime candidate for construction materials, particularly walls and flooring, or as aggregate material for road paving. It has also be used as armor rock for sea walls, as well as ornamental stones in gardens.
Greywacke Market Value Calculator
Estimate the market value of Greywacke using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.
Greywacke Localities Map
See where Greywacke is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.
Key Characteristics
Clasts of Greywacke
Quartz, lithics, minor feldspar ( orthoclase, plagioclase), pyroxene ( augite), mica (biotite, chlorite, muscovite); often quartz veins visible
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Quick Facts
Physical Properties
- Color
- Gray to black, brown, yellow, etc.
- Hardness (Mohs)
- 6 - 7
- Density
- 2.6 - 2.61 g/cm³
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