Basalt, Dolerite is a medium to fine grained hypabyssal rock. It is found in sills and dykes. It has dark gray or sometimes black texture. It is composed of Plagioclase, Augite and Iron Oxide with some Olivine. Dolerite is an intermediate rock between Gabbro and Basalt.
As the texture increases in its coarseness, it approached Gabbro and as the texture becomes finer, it approaches Basalt.
Basalt is used in many countries, especially in highway and airfield pavement construction and machinery to crush basaltic rocks into construction size aggregates, and this makes them easily abundant. In conventional concrete mixes used in the construction industry.
Uses of Dolerite - Due to interlocking of crystals, the rock is very tough and is widely used as a road metal. It has a quality of making firm grip with coal tar. Extensively used as aggregate for concrete work. In its unearthed state, Dolerite or Gabbro is igneous rocks among one of the strong building stone for Rock fill, shore protection, break water, rock revetments.