Answer:
Calcite
Step-by-step explanation:
Calcite is a mineral formed by calcium carbonate (CaCO3), class 05 of the Strunz classification, the so-called carbonate and nitrate minerals.
All members of this group crystallize in the trigonal system, have a perfect rhombohedral cleavage and exhibit a strong double refraction in transparent rhombohedra.
It presents a variety of shapes and colors. It is characterized by its low hardness, 3 on the Mohs scale, and by its high reactivity even with weak acids.
The best property to identify calcite is the acid test, since this mineral produces effervescence with acids. The reason for this is the following reaction:
CaCO3 + 2H + → Ca2+ + H2O + CO2 (gas)