Marble is a metamorphic rock that derives from the metamorphism of carbonate rocks like limestone, dolomite, and marl. Marbles consist of more than 50% of carbonate minerals (calcite, dolomite), which can coexist with various silicates and other minerals depending on the protolith and the metamorphic grade reached. Marbles are said to be pure if the content of carbonate minerals > 95%, whereas they are impure if it is comprised between 50 and 95%. According to the IUGS, a rock with less than 50% of carbonates is not a marble, but a carbonate-silicate rock.