Flagstone is almost always a Sandstone. Flagstone refers to the cuts and the installation with large irregular shaped pieces of stone and large grout lines. Any stones can be cut and installed as a Flagstone pattern. Sandstone is a sedimentary stone that is deposited as mountains are turned into sand grains by erosion. After time, the sand grains are compacted together and bonded together by minerals to form a solid rock.
There are several different types of Sandstone depending on where it is mined from the earth. All Sandstone is extremely porous and susceptible to staining, water erosion, mineral deposits on the surface, and efflorescence from within the stone. Sandstone is not susceptible to etching. Common uses for Sandstone installed in the Flagstone pattern: Exterior deck covering, interior floor covering, swimming pool deck surrounds.