Stone

Building structures from stone is the foundation of masonry. Stone has been used in structures for thousands of years. Although modern materials have become a dominant choice in the building and construction industry, stone still has a place for it's qualities of durability, beauty, and representation as an iconic material.

Stone can come in three naturallly different forms:

• Igneous stone comes from the cooling of magma, following a volcanic eruption or magma flows within the Earth's crust. Igneous stone is often hard and non-pourous.
• Sedimentary rock is relatively soft compared to other types of stone, and comes from deposits of erosion which settled into layers and became compressed over time. Sandstone and limestone are good examples of sedimentary rock.
• Metamorphic rock is also hard and non-pourous but comes from rock that was changed by compression, heat, or other geological factors. Marble is a distinct example of metamorphic rock; it most samples of marble you can see the variations and flaws that represent the change.

These different types of stone lend themselves to different applications. For example, because sedimentary rock is softer than igneous or metamorphic stone, it would not be the best choice for a retaining wall, or in applications that involve running water.

Much of the stone used in construction comes from quarries, that exist as a part of mining for some other mineral, or are a source of a particular stone to begin with. The stone pulled from these chasms in the earth's crust is very "raw", and may be sent to a masonry to be refined or shaped, especially in the case with marble.