Often used to break up hard material, such as rocks or concrete.

Floor, ceilings, walls, they were all made of the same hard material.

In this form it is a small, hard material.

The ceiling, walls and floor were the same hard, gleaming white material.

These come in various shapes and can made of hard or soft materials.

For example, when hard materials are cut, the diamonds should be smaller.

Glass is a hard material that can be made in many shapes.

It is used to cut through relatively hard material, most often wood.

Decades or centuries of use had stained the hard white material.

A coin is a piece of hard material used as money.