Explanation
A basic extrusive rock. The composition is equivalent to gabbro, and it is one of the most widely distributed rock in extrusive rock. It is mainly composed of basic plagioclase and pyroxene, and the secondary minerals are olivine, sometimes amphibole, biotite, and a small amount of quartze when the silica is supersaturated- It is generally grayish black in color. porphyritic texture is common, and phenocryst is olivine, pyroxene, basic plagioclase, etc. The matrix is generally fine particles, sometimes aphanitic or glass, with interstitial structure, tholeiitic structure, coarse basaltic structure, diabase structure, etc. vesicular structure and amygdaloidal structure are common, and hexagonal columnar joints are developed. Large areas of rock often break out. It can be used as the main raw material of caststone, rock wool and scales. Marine eruptive basalt is often associated with Cu and Fe deposits. Fresh and dense, with a compressive strength of 350-500MPa, it is a good building decoration materials and a raw material for bituminous concrete pavement materials of expressway.
Classification
Natural materials and products -> Mineral materials