Dolerite
Dolerite which is also known as diabase, is a widely distributed and extremely common igneous rock. It is a course grained, intrusive form of basalt, and there are several different kinds, including quartzdolerite, mica-dolerite, porphyrite-dolerite, and olivine-dolerite. They occur as dykes and sills, and all are primarily composed of the typical basaltic minerals, alson with others such as biotite, hornblende, and apatite. Dolerite is not a particularly attractive material, and so is only used for low-grade construction applications like road building. With a specific gravity of around 3.0, it is a relatively dense rock.
| Color: |
Red-brown to black |
| Origin: |
Intrusive |
| Grain size: |
Medium |
| Occurence: |
Worldwide as dykes and sills. |