Letter Grade 4.0 Point Scale (+/-) A+: 4.0: A: 4.0: A-3.7: B+: 3.3: B: 3.0: B-2.7: C+: 2.3: C: 2.0: C-1.7: D+: 1.3: D: 1.0: D-0.7: F: 0.0
Coral calcium is a salt of calcium derived from fossilized coral reefs (primarily from limestone and coastal deposits).It has been promoted as an alternative, but unsubstantiated, treatment or cure for a number of health conditions.oral calcium is a source of calcium, which is an essential mineral for human life. Coral has a chemical structure that is very similar to the composition of human bone and is sometimes used as material in bone grafts.
1 Coral polyps are tiny animals that build protective calcium carbonate skeletons. 2  Coral polyps create the basic structure of coral reefs with the help of single-celled algae.