Diabase, also known as Fujian Qing, Dahu Qing and Qingshi, is an epigenetic diabase equivalent to gabbro. Crystalline, fine - medium grain, dark gray - gray black, often with a green or secondary green structure. Dark grey and gray black. Diabase is mainly composed of pyroxene and basic feldspar (epigenetic rocks with the same composition as gabbro). It contains a small amount of olivine, biotite, quartz, apatite, magnetite, ilmenite and so on. Basic plagioclase is often altered into albite, epidote, epidote and kaolinite, while pyroxene is often altered into chlorite, amphibole and carbonate minerals. The whole color of chlorite is usually greyish green. Diabase is similar to gabbro in composition, but it is shallow and not as deep as gabbro, so it is smaller in grain size, and it does not erupt from the surface like basalt and is mainly glassy. Diabase can be divided into olivine diabase, quartz diabase, zeolite, orthoclase, alkaline diabase and so on according to the different secondary minerals.