Stone

**Stones**
Stones are solid minerals that come from nature. They are many types of rocks according to their composition, for example they are igneous rocks, sedimentary rocks, and metamorphic rocks. This clasification originates from the caracteristics of the rocks: like the chemical composition, texture and others. Te Igneous rocks: These are the oldest type of rocks. They originate from the magma. As the magma pushes the earth`s surface, it starts to cool and turns into solid igneous rocks. The Sedimentary rocks: Many sedimentary rocks are made from the broken bits of other rocks. The sediment may, in time, form a rock if the little pieces become cemented together. The Metamorphic rocks: These rocks get their name because they "morphed" into another tipe of rock. Tons of presure or temperature causes them to change.

Stones have been use in constuction since the origin of life. They were used by the prehistoric man to build weapons, caves and shelters. They are used in construction for many features: they are obtained from nature, also their durability, adaptability and so on. They were very useful especially in times were they was not many materials to choose from, or they were not very resistent, but they can still be used for there construction values.