Flagstone is a natural stone that is typically sold in an irregular, inconsistent flat shape and no two stones seem to be alike. However, flagstone can also be cut into tile stones. It’s thickness usually ranges from 1 to 2 inches. It is durable and can be used both indoors and outdoors. Typically used for walkways and patios. It’s greatest advantage being able to create an enhanced one-of-a-kind look.