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.
The geological record indicates that the ancestors of modern coral reef ecosystems were formed at least 350 million years ago. The coral reefs existing today began growing as early as 50 million years ago. Most established coral reefs are between 5,000 and 10,000 years old.Although size can be a good indicator of the age of a coral reef, it is not a certain indicator.he geological record indicates that the ancestors of modern coral reef ecosystems were formed at least 350 million years ago. The coral reefs existing today began growing as early as 50 million years ago. Most established coral reefs are between 5,000 and 10,000 years old.