As said above, granite must be at least 20% quartz, which means an all black rock is not a granite. Most commonly, black granite is in fact gabbro, a mafic intrusive igneous rock similar to basalt.

Ocean drill reaches unprecedented depth LiveScience: Scientists have drilled nearly a mile into the planet's ocean crust, retrieving samples from the pristine layer of igneous rock for the first time.

Scientists onboard the drilling ship JOIDES Resolution in the Pacific Ocean, about 500 miles west of Costa Rica, bored into the planet's crust and recovered black rocks called gabbro from intact ...

The Atlantis Massif is an oceanic core complex at 30°N on the Mid-Atlantic Ridge on the north side of the Atlantis I transform fault, which offsets the ridge by ~60 kilometers. The massif is capped by ...

Find out how magma has created igneous rock features with this BBC Bitesize Scotland article for P5, P6, P7 - Second Level CfE ...

News Published: 24 March 1934 Petrogenesis of the Newry Igneous Complex Nature 133, 467–468 (1934) Cite this article ...