What is the Difference Between Calcite and Dolomite?

Calcite and dolomite are both carbonate minerals, but they have some differences in their structures and properties:

1. Structure: Calcite has a trigonal structure with two molecules per unit cell, while dolomite has a hexagonal structure.
2. Composition: Calcite mainly contains calcium carbonate (CaCO3), while dolomite contains calcium magnesium carbonate (CaMg(CO3)2).
3. Hardness: Calcite has a hardness of 3 on the Mohs Scale, while dolomite has a hardness of 4-4.5.
4. Crystal Forms: Calcite often forms scalenohedral or "dogtooth" crystals, which are not found in dolomite. Dolomite crystals can show slightly curved surfaces due to the atomic size difference between calcium and magnesium atoms.
5. Acid Reaction: Calcite reacts vigorously with acids, producing carbon dioxide bubbles. Dolomite, on the other hand, reacts less vigorously with acids, producing bubbles very slowly.
6. Raman Spectroscopy: The vibrational modes of the carbonate groups in calcite and dolomite can be distinguished using Raman spectroscopy, which shows differences in the bands observed.

In summary, calcite and dolomite are both carbonate minerals with some similar properties, but they differ in structure, composition, hardness, crystal forms, and acid reactions.

Comparative Table: Calcite vs Dolomite

Here is a table comparing the differences between calcite and dolomite:

Both calcite and dolomite marble tiles are used in decorating homes and other spaces due to their high durability and visual appeal. However, dolomite marble tiles are more scratch-resistant and less reactive to acids compared to calcite marble tiles. Additionally, dolomite marble tiles come in a wider range of colors, while calcite marble tiles are typically clear, white, or have impurities like iron oxide.