Coral - a hardened marine plants.

Most of the coral has a smooth surface. But among them there are those on which, if properly considered, according to length, there are subtle grooves. They resemble the wrinkles that are present on the inner surface of the fingertip. In the center they are in the form of elongated concentric circles. Then there are the grooves coming from both sides of the coral. They form a sort of triangle, curved in the shape of a bow. There is also the white coral - the lowest grade of this mineral. He is a little thicker and coarser than the red, has no dents, like the traces of smallpox. It has a yellowish tint. In our time, scientists have identified as sea coral stone, consisting of calcium carbonate of iron oxide and organic matter. At sea corals are found in white, pink, red and other colors. The most prized pink coral They are not transparent and less brittle than the amber and pearls. Of coral make various ornaments and jewelry.