One of the earliest materials used for building, stone continues to be commonly used today. However while it has traditionally been used for structural purposes, today it is more often used instead as a non-structural surface material.
As a structural material, stone is quite strong in
compression, but is britle and is not nearly as strong in
tension. The relative weakness of stone when under tension is what led to the invention of the
arch.
The natural variations in its surface
color and
texture also make it a common choice as a surface material, in both natural and polished forms.