Diorite
Rock made of plagioclase, hornblende
Common
A coarse-grained rock between granite and gabbro, of sodium-rich plagioclase with hornblende and biotite, often sold as "black granite". The Akkadians of Sargon carved their funerary statues in it.
Rock
- Kind of rock
- Plutonic igneous rock
- Rock family
- Granite
- Texture
- coarse-grained
- Also contains
- Mica, Pyroxene
- How it forms
- Magma of intermediate silica, from the partial melting of mafic rock above a subduction zone, cools slowly in the roots of volcanic arcs and mountain belts such as the Andes.
- Uses
- Decorative and sculpture stone since prehistory; today aggregate, curbs, cobbles and facing stone.
Crystallography
- Habits
- Granular, Massive
Physical properties
- Luster
- Vitreous
- Colors
- gray, black, white
- Transparency
- Opaque
Geology
- Origins
- Igneous
- Geography
- worldwide
Classification
- Rarity
- Common
- Gem quality
- No
Sources
- Diorite. Wikipedia.
- M. R. Gillespie, M. T. Styles, BGS Rock Classification Scheme, Volume 1: Classification of igneous rocks (Research Report RR 99-06). British Geological Survey, 1999.
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