Stone

A stone is a piece of rock. It is a mass of hard, compacted mineral. The word is often used to mean a small piece of rock.

The word "stone" also refers to natural rock as a material, especially a building material. Natural stones used as building material include granite, marble and sandstone. Manufactured, artificial products, such as concrete or clay bricks, are not stone.

Stone takes a while to heat up, and stays hot for a while. It does not conduct electricity well.

Stone was one of the first materials used to make tools and buildings. It is a very sturdy material. It is less affected by weather than wood or brick. Depending on the type of rock, stone weathers away much more slowly. A stone in the river is reshaped by the water and sediment flowing around it.

Stones can be used as primitive weapons. A person can throw it at an enemy or animal, or use it to cause more damage in hand-to-hand combat.

A stone is larger than a grain of sand, gravel or pebbles. A boulder is a large rock or stone.