Basalt is a dark, fine-grained igneous rock that is composed of minerals such as plagioclase and pyroxene. It is durable, does not react to acids, absorbs sound, and has consistent coloring. This stone has a variety of end uses including building veneers, floor and wall tiles, wet areas, countertops, asphalt pavement aggregate, monuments, and railroad ballast.
Basalt is Earth’s most abundant bedrock and it is derived from lava flows and oceanic hotspots. When lava erupts from a volcano and trails to a flatter continent where it is able to cool, it forms rock. In the case of basalt, the lava is flowing into seas and forms under water. Very little basalt can be found on continental land that is not near a body of water.
Basalt can also be formed through oceanic hotspots in which continuous eruptions on the ocean floor build the volcanic cone up higher until it becomes a large, solid mass. An example of this is seen with all of the islands that make up Hawaii. These islands are composed of basalt stone that were formed during multiple eruptions on the sea floor.
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