causing them to change into another type of rock. They are usually resistant to weathering and erosion and are therefore very hard-wearing. Examples of metamorphic rocks include marble ...

There are lots of types of rock and each type has different properties and uses. For example, some are strong and hard but others are soft and sandy. Some rocks are harder than others. For example ...

In this article, we'll list 30 types of rock with pictures and a brief description to help you identify them.