What Kind of Rock Is Blue Dolomitic Limestone?

Sedimentary, Igneous or Metamorphic

• Most sedimentary rocks are created when many layers of silt or small pieces of weathered rock are deposited in one area over a long period of time. The accumulated moderate pressure of the accumulated layers presses sediment into rock form. igneous rocks, on the other hand, are born from the fiery depths of a volcano. As the volcanic magma pours from the earth, the liquid crystallizes as it cools forming igneous rocks. Metamorphic rocks start as either sedimentary or igneous rock and then are subjected to intense heat and pressure, changing to coarse-grained rocks. Blue dolomitic limestone is a sedimentary rock.

Clastic, Organic or Chemical

• Blue dolomitic limestone is an organic sedimentary rock, that is one created by the accumulation of biological layers, such as shells and plant tissue. Chemical sedimentary rocks are formed by a supersaturated solution that produces crystals as the liquid evaporates or cools, such as rock salt. Clastic is the third type of sedimentary rock, from deposits of other weathered rocks.

Mineral Composition

• You can classify sedimentary rock by the chemical composition of its primary elements. Blue dolomitic limestone is a carbonate sedimentary rock. Chemical composition examples include silica-based sedimentary rocks known as siliceous, silicate based rocks known as siliclastic and phosphatic rocks composed of phosphate, iron-rich sedimentary rocks such as ironstones and organic-rich sedimentary rocks such as coal. Other composition-based classifications of sedimentary rocks include evaporative rocks such as gypsum and siliciclastic rocks composed of silicates rather than the silicas.

Dolomitic Limestone

• The composition of dolomite is calcium magnesium carbonate, while limestone is composed of calcium carbonate. Dolostone is a mixture of dolomite and limestone where the ratio of calcium magnesium carbonate crystals to calcium carbonate molecules is greater than 1 to 1. When the ratio is less than 1 to 1, where only a small portion of calcium magnesium carbonate replaces calcium carbonate, the rock is known as dolomitic limestonem which is rock is a blue-grey color; the blue color intensifies with increased organic components.