Marble is a widespread metamorphic rock. Depending on whether marble has been formed from limestone or dolostone, marbles consist either of calcite or dolomite. Additionally, marble may include quartz, garnet, serpentine, etc.
The colour of marbles is extremely variable — from light white to black. Marble rocks are white, bluish-grey, pink, brown, multicoloured dappled or banded rocks. Marble has often a flow texture, which is formed due to the movement of partially melted rocks in relation to each other during the metamorphism.
Marble consists mainly of calcite, the hardness of which is 3, which is why marble can easily be scratched with a needle. Marble also reacts with acids, for example, with hydrochloric acid, which when dripped on marble causes a fizzy reaction where carbon dioxide separates.
For commercial purposes, several sedimentary rocks are sometimes also sold under the name marble.
Marble rocks are easily polishable and for this reason they are used as construction and finishing materials as well as decorative stones both in architecture and sculpture.
Marble’s specific gravity is 2.65…2.80.