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, ... Red Granite. Red granite (Credit: eurasian.com) ...

As NASA’s MAVEN mission heads toward Mars, scientists say they’ve discovered highly unusual, light-colored rock on the mostly dark-toned Red Planet – and two teams have dueling ideas of what ...

Maine granite rocks! While Maine's pegmatite can be prettier and may become the state's official rock, its tougher cousin, granite, has been creating and beautifying buildings and monuments across ...