| Rock class: | Intrusive Igneous Rock |
| Composition: | Plagioclase and clinopyroxene. Either with olivine (Olivine gabbro) or without (Ophiolitic gabbro). |
| Color: | Green, Grey, Brown |
| Specific Gravity: | 10 |
| Grain: | Coarse (Ophiolitic) or Medium (Olivine) |
| Environment: | Ophiolitic gabbro forms between the ultramafic substratum near the mantle and overlying basaltic lavas, presumably crystallized at depth during the opening of an oceanic basin. |
| Comments: | Common in the Alps; Arran, Scotland; Cyprus and the eastern Mediterranean. Fragile, sometimes associated with copper mineral deposits. Olivine gabbro is found in South Africa, the Harz Mountains of Germany, and North America. |