Basalt is one of the most important and common extrusive volcanic rocks. Based on how rapid cooling of lava at the surface of earth is, it usually is in grey to black colors.

Basalt is an igneous rock and it is mainly composed out of plagioclase and pyroxene minerals, similarly to gabbro. the difference between them is that basalt has a fine-grained texture while gabbro is a coarse-grained rock. Basalt can form as an extrusive rock from lava flow or it can form in small intrusive bodies like a thin sill. One of the important facts about basalt is that it is the most abundant bedrock on earth which means that it covers the most of the surface of earth. For instance, ocean basins most areas are underlain by basalt. However, it is not a common rock on surfaces of the continents. An interesting fact about basalt is that, it also covers the Moon and much of the Moon’s surface is made out of flood basalts or basaltic lava flows. These areas on the Moon are called “lunar maria.” Basalt on Earth can mostly be found on three environments, In order of oceanic divergent boundaries, oceanic hotspots, and mantle plumes or hotspots under the continents.

Basalt has wide range of uses. The crushed form of it can be used as an aggregate in construction projects, road beddings, concrete aggregate, asphalt pavement aggregate, railroad ballast, filter stone and may other purposes. It also can be cut into dimension stones and polished for uses such as floor tiles, building facades, monuments, and even art.