Black granite

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Black granite is a common name for dark, very hard rocks used in construction. These rocks are strong and durable, similar in strength to granite, and are often used for countertops, floors, and outdoor surfaces. Geologically, rocks labeled as black granite can include gabbro, diabase, basalt, diorite, norite, or anorthosite. Not all of these are true granite, which is normally light-colored and contains quartz. The term "black granite" is mostly a commercial label, and the exact rock type can vary.