Properties of Dolomite Powder
Modern sedimentary environments rarely include dolomite, although dolostones are widely distributed throughout the rock record. They may cover a wide geographic area and range in thickness from hundreds to thousands of feet. The majority of dolomite-rich rocks were originally calcium carbonate muds that underwent postdepositional alteration by pore water rich in magnesium to become fine dolomite powder.
Another typical mineral found in hydrothermal veins is dolomite. It frequently coexists with barite, fluorite, pyrite, chalcopyrite, galena, or sphalerite in that location. It frequently appears as rhombohedral crystals with occasionally curved faces in these veins.
| Chemical Classification | Carbonate |
| Color | Colorless, white, pink, green, gray, brown, black |
| Streak | White |
| Luster | Vitreous, pearly |
| Diaphaneity | Transparent to translucent |
| Cleavage | Perfect, rhombohedral, three directions |
| Mohs Hardness | 3.5 to 4 |
| Specific Gravity | 2.8 to 2.9 |
| Diagnostic Properties | Rhombohedral cleavage, powdered form effervesces weakly in dilute HCl, hardness |
| Chemical Composition | CaMg(CO3)2 |
| Crystal System | Trigonal |
| Uses | Construction aggregate, cement manufacture, dimension stone, calcined to produce lime, sometimes an oil and gas reservoir, a source of magnesia for the chemical industry, agricultural soil treatments, metallurgical flux |
The table on this page lists the dolomite's physical characteristics that are helpful for identification. Dolomite has three ideal cleavage directions. When the dolomite is fine-grained, this may not be noticeable. However, when it is coarsely crystalline, a hand lens can be used to easily see the cleavage angles. Dolomite occasionally appears as rhombohedral crystals with bent faces and has a Mohs hardness between 3 1/2 and 4. When exposed to cold, diluted hydrochloric acid, dolomite reacts extremely weakly; however, if the acid is warmed up or if the dolomite is powdered, a significantly greater acid response will be seen. (Scratching dolomite on a streak plate can quickly turn it into powder.)
Dolomite and the mineral calcite are quite similar. Dolomite is a calcium magnesium carbonate, whereas calcite is made of calcium carbonate (CaCO3). One of the most frequent mineral pairs poses a problem for mineral identification in the field.
The hardness and acid response of these minerals can be used to distinguish them from one another. Dolomite is slightly harder than calcite, which has a hardness of 3 to 3 1/2. Dolomite will only mildly effervesce in the presence of cold hydrochloric acid, in contrast to calcite, which is likewise strongly reactive.
Dolomite rock is composed mainly of the mineral dolomite and contains contaminants such as calcite powder, quartz sand, and feldspar.
There are not many uses for dolomite as a mineral. However, because it can be mined, dolostone is found in deposits that are big enough to mine.
Dolostone is most frequently used in the building sector. It is crushed and graded for use as fill, rip-rap, railroad ballast, concrete and asphalt aggregate, and road base material. In order to make cement, it is also calcined and carved into "dimension stones," which are blocks of a specified size. Dolomite is useful because of how it reacts with acid. In the chemical business, for soil conditioning, stream restoration, and acid neutralization, are employed.
Magnesium (MgO) is found in dolomite, which is also used to make glass, bricks, and ceramics. It is also utilized as a sintering agent and flux in the manufacture of metals.
Numerous lead, zinc, and copper resources are hosted by dolomite. These deposits are created when hot, acidic hydrothermal fluids rise from the depths and encounter a unit of dolomitic rock. The dolomite reacts with these solutions, resulting in a pH reduction that sets off the precipitation of metals from the solution.
A rock used as an oil and gas reservoir is dolomite. Volume is decreased when calcite is transformed into dolomite.
As a result, the rock may develop pore openings that allow the migration of oil or gas released from neighboring rock units. Because of this, drilling for oil and gas frequently targets dolomite as a reservoir rock.
