Sandstone

Mention the word sand and many people will think of desert and beaches. They may also think of sandstone, a sedimentary rock that is made of grains of sand. Sandstone forms in a range of environments and is often used as a building stone.

Limestone

The remains of ancient creatures make up many types of limestone. Other varieties form when minerals precipitate out of water. All limestones. however, form where water is present and consist mainly of calcite. The main uses of limestone include building stone, cement, and fertilizers.

Granite

Typically, granite is a tough rock that forms pronounced topographical features and is resistant to erosion. It forms by the slow cooling of magma deep in the Earth's crust, and is composed of silica-rich minerals such as quartz, feldspar, and smaller amounts of mica and amphibole (generally hornblende).

Basalt

The most common igneous rockon the Earth's surface, basalt forms the rock floor of most of the oceans. It also occurs in continental settings as extensive plateau basalt, such as in the Columbia  River region of the northwest US. In both settings, basalt is found as intrusive and extrusive bodies of rock