Limestone and calcitic marble can be easily confused for one another because both are composed of the same...?

Question

mineral. What are two ways which the two rocks may be distinguished?

Answer 1

Both are composed of calcite, with limestone being the pure from. Marble is a metamorphic rock composed mostly from limestone (the protolith) that is heated and pressurized, which destroy fossils and sedimentary textures, which makes it smoother and polished.

The are distinguished by the composition and their texture.

The main difference is limestone is more pourous because it was
formed when shells, sand, and mud at the bottoms of bodies of water over time that solidified and there are openings between between the fossil fragments.

Marble formed by having that limestone pressured and heated by the weight and gravity of that sedimate over time that crystalizes it. Marble is denser and smoother because those fossil fragments have been pressed together. As marble can be a mix of colors and streaks because it contains non-calcitic minerals in addition to the limestone.

Answer 2

limestone are both composed of calcium carbonates. they only differed by the timeof its formation.

limestone is a sedimentary rock while marble is a metamorphic rock.

another distinguishing character of the two:

limestone is harder than marble. you can easily scratch marble by your finger nails, while it will take you whole of your finger nails to make a little scratch on limestone surface.

Answer 3

Calcium Carbonate ( CaCO3 ) Calcitic marble is harder.