Answer :
Final answer:
Limestone is primarily composed of calcite and often includes organic materials from marine organisms. A rock is classified as limestone if it contains at least 50% calcite. These characteristics are essential in identifying limestone in geological studies.
Explanation:
What Organic Materials Make Up Limestone?
Limestone is primarily composed of the mineral calcite, which is a crystalline form of calcium carbonate (CaCO3). It often contains organic materials such as the remains of marine organisms like corals, shells, and foraminifera. These organisms contribute to the overall structure and composition of the rock.
Determining Factors for Limestone
To classify a rock as limestone, it must contain at least 50% calcite. If a rock contains this percentage of calcite, it is classified as limestone, whereas lower percentages indicate that it could be another type of rock.
