Mineral Composition:
* Gabbro: Predominantly composed of pyroxene and plagioclase feldspar, with lesser amounts of olivine, amphibole, and iron-titanium oxides.
* Granite: Primarily composed of quartz, feldspar (both orthoclase and plagioclase), and mica (biotite and muscovite).
Texture:
* Gabbro: Phaneritic texture, meaning the mineral grains are visible to the naked eye and are roughly equal in size. This results from slow cooling and crystallization deep within the Earth's crust.
* Granite: Also phaneritic, with visible mineral grains. However, granite often has a slightly more course-grained texture than gabbro.
Other Differences:
* Color: Gabbro is typically dark-colored (black, gray, or green), while granite is usually light-colored (white, gray, or pink).
* Density: Gabbro is denser than granite.
* Origin: Gabbro forms from the slow cooling of mafic magma (rich in magnesium and iron) in the Earth's crust. Granite forms from the slow cooling of felsic magma (rich in silica) at a shallower depth.
In summary:
While both gabbro and granite are igneous rocks, their mineral compositions and textures are distinctly different. Gabbro is a mafic rock with pyroxene and plagioclase feldspar as dominant minerals, while granite is a felsic rock with quartz, feldspar, and mica as primary constituents. Both rocks have phaneritic textures, but granite tends to be more coarse-grained.
