Coral is the skeleton of many small marine animals , living together, having formed a colony. These animals belong to the class of polyps anthozoa, size a few millimeters each, living next to each other forming massive colonies. Each polyp born, crashes its skeleton in the colony and expands . These colonies during the centuries can reach kilometers in length forming coral reefs which are called atolls. Coral reefs consist of calcium carbonate , CaCO3, the material from which the skeleton of each tiny polyp is made. In the colonies along with coral polyps live and some monocytic algae called zooxanthelles . These algae photosynthesize and supply food to the polyps , but at the same time secrete pigments which color the colonies, ie corals. Corals have a hardness of 3.5 and a specific weight of 2.6.

It is considered to be a very powerful talisman. In many regions of Greece people believe that coral protects against the evil eye, as well as sailors from the fury of the sea. In Chios isle they hung sprigs of coral in the crib of the newborn. Finally we mention that in many renaissance paintings the divine infant is depicted with a sprig of coral, hanging on the neck. The word coral has probably Greek etymology : cori – alos , ie , the daughter of the sea.

The fisheries and trade in coral , are an activity governed by the ” Convention on the International Trade of Endangered Species” (CITES). This treaty has been signed by 154 countries, allowing where to catch the various qualities corals. The annexes to the Treaty, detailing the areas and qualities coral fishing is authorized.