igneous
Diorite
Diorite (Intrusive igneous rock)
Hardness: 6-7 on Mohs scale; Color: Salt and pepper (mottled black and white); Luster: Phaneritic (crystalline); Crystal structure: Coarse-grained; Specific gravity: 2.8-3.0.
- Hardness
- 6-7 on Mohs scale
- Color
- Salt and pepper (mottled black and white)
- Luster
- Phaneritic (crystalline)
Identified More igneous →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 on Mohs scale; Color: Salt and pepper (mottled black and white); Luster: Phaneritic (crystalline); Crystal structure: Coarse-grained; Specific gravity: 2.8-3.0.
Formation & geological history
Formed by the slow cooling of magma beneath the Earth's surface in volcanic arches and subduction zones. Typically associated with continental crust formation.
Uses & applications
Used in construction as crushed stone for roads and drainage, as decorative dimension stone for countertops and tiles, and historically for sculptures.
Geological facts
Diorite was used by ancient civilizations like the Egyptians and Sumerians to carve statues and inscriptions because of its extreme hardness and durability.
Field identification & locations
Identify by its 'salt and pepper' appearance with roughly equal amounts of light plagioclase feldspar and dark minerals like hornblende or biotite. Commonly found in large mountain ranges like the Andes.
