Coral is the skeleton of many small marine organisms that comprise a colony. These organisms are polyps, each a few millimeters in size. When a new polyp is born, it attaches its skeleton to the colony and thus expands it. In coral colonies, along with the polyps, some single-celled algae coexist, which photosynthesize and supply food to the polyps, and at the same time secrete pigments that color the colonies, i.e. the corals. Corals can appear in a wide variety of colors such as pink-red, beige, white, as well as black (Yusuri coral). It is supposed to fend off negativity and enhance sexuality.
Inclusions, cracks and breakage surfaces are a natural phenomenon and should never be associated with wear and tear.