Granite is lighter in color than basalt. The color of the rocks is dependent on the mineral composition of the rocks. Basalt is basic and contains a substantial amount of olivine whereas granite is acidic and is rich in quartz.
Basalt is an intrusive igneous rock with small mineral crystals, formed when magma cools and solidifies rapidly; this is usually on the surface of Earth's crust, especially at incidents of seafloor spreading on the ocean floor as contact with seawater cools the magma rapidly.
Granite is the foundation of the continental crust. Basalt is the foundation of oceanic crust.
Granite is an extrusive igneous rock made from visible mineral crystals, a result of cooling over a longer period of time under the surface of the Earth.
Another difference between basalt and granite include their joints. Basalt splits along columnar planes while granite splits along horizontal planes. This difference is due to the difference in their cooling process.
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