Limestone is typically formed over many years at the bottom of oceans or lakes from the accumulation of shells, bones and other calcium rich goods. If this limestone is subjected to intense heat or pressure and a few millennium, a crystallization will occur and the limestone will become a "true marble." Chemically they are both still calcium carbonate, but the marble will have a crystalline structure and the limestone will have a relatively flat appearance.

Limestones that will take a polish are considered marbles by most people, but technically, if there are still shells visible or the structure is not crystalline, it is still a limestone.

Limestones that have magnesium in them are called "dolomitic limestones" and are typically much harder and more resistant to weathering. A typical characteristic of dolomitic limestone are their capability of taking a flame-finish.

Limestones are typically used for flooring, wall cladding, vanity tops, furniture and often times, ornate stonework.