Coral knowledge-baolong.com Baolong.com Colored Gem Knowledge-Coral Coral is an organic gem among colored gems, and it is a calcium carbonate skeleton secreted by corals of marine animals. Corals grow on the bottom of the sea and are shaped like branches and flowers. The processed corals are often made into necklaces, βραχιόλια, καρφίτσες, ornaments and other […]
