If you are referring to igneous rocks, they are classified as mafic.
Granitic igneous rocks are light colored rocks of a low density. Granitic magma is thick and stiff and contains a lot of silicon and oxygen. Granitic magma can build up a great deal of pressure, which is released during violent volcanic eruptions.
Dense. Light colored igneous rocks have lower density compared to dark colored igneous rocks due to their higher silica content, which results in slower cooling and the formation of larger crystals.
Because of natural selection, most of the light-colored mice live on light rocks, while most dark-colored mice live on dark lava rocks.
Basaltic Magmas are dark colored, heavy and are ferromagnesian in composition, so they most times do not form light colored rocks, rather, the Felsic Granitic Magma forms the light colored rocks with lower densities.
Light-coloured igneous rocks, such as granite, have a higher silica content and lower iron and magnesium than darker ones, such as basalt. Since iron and magnesium are very dense minerals, this makes darker igneous rocks more dense than lighter ones.
igneous
Granitic igneous rocks are light colored rocks of a low density. Granitic magma is thick and stiff and contains a lot of silicon and oxygen. Granitic magma can build up a great deal of pressure, which is released during violent volcanic eruptions.
The dark colored mica is called biotite. It is a common mineral found in igneous and metamorphic rocks and is known for its dark brown to black color.
Normally, light colored igneous rocks are less dense compared to dark colored igneous rocks. This is because the light colored rocks have a less iron in them.
Normally, light colored igneous rocks are less dense compared to dark colored igneous rocks. This is because the light colored rocks have a less iron in them.
less dense
Mafic igneous rocks, like basalt, are dark colored and low in silica.
Most dark-colored igneous rocks are mafic, which means they are rich in minerals like pyroxene, olivine, and amphibole. These minerals give the rocks their dark color due to higher iron and magnesium content. Additionally, dark-colored igneous rocks are typically extrusive, forming from rapid cooling at the Earth's surface.
Dark colored rocks.
As a first approximation, the colour of igneous rocks gives an estimate of the concentration of iron in it. Very dark igneous rocks commonly a large fraction of minerals with iron as a major constituent. As those minerals are denser than most other silicate minerals occuring in igneous rocks, dark colored igenous rocks are usually denser than the ligher ones.
Mafic igneous rocks, like basalt, are dark colored and low in silica.
Most dark-colored igneous rocks have a high density.