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.
(Coral skeleton is white because it is made of calcium carbonate, a mineral also found in chalk and human bones.) The green beach on the big island of Hawaii is green because the particular kind of rock that formed the sand (a type of cooled lava called basalt) has high amounts of a green mineral called olivine.