Coral purification method and coral thus obtained

The present invention provides a method of extracting organic substances present in coral, which consists in treating the coral with a fluid or a mixture of fluids in the supercritical state without modifying the crystalline structure of said coral, at a temperature of less than 270° C. and at a pressure which is much higher than the critical pressure of said fluid or mixture of fluids, for example of the order of at least 3 times, and preferably at least 5 times said critical pressure. It also provides coral obtained by said method and bone substitutes fabricated from said coral.