A '''Xenolith''' is a smaller piece of [[rock]] that is encorporated into a larger rock. Xenoliths form when [[magma]] flows round a piece of rock and hardens. Xenoliths are clearly different from the rock that surrounds them. | A '''Xenolith''' is a smaller piece of [[rock]] that is encorporated into a larger rock. Xenoliths form when [[magma]] flows round a piece of rock and hardens. Xenoliths are clearly different from the rock that surrounds them. |