How will the appearance of the dolerite and gabbro differ?

Dolerite, also known as basaltic diabase, typically has a finer-grained texture due to its formation from magma that cooled rapidly, often observed in vertical columns or dikes. It usually appears dark in color, with a predominantly black or gray hue. In contrast, gabbro has a coarser texture because it forms from magma that cools slowly beneath the Earth's surface, allowing larger crystals to develop. Gabbro typically exhibits a similar dark coloration but with visible crystals of minerals like plagioclase and pyroxene, giving it a more granular appearance.