Coral is a living marine organism that forms in branch-like structures in tropical and sub-tropical ocean waters. When coral polyps die, a dull, hardened skeleton remains that can be polished to a beautiful waxy luster. Most coral is white to cream in color but it does occur naturally in several other colors such as red, pink, peach, black, orange, golden, blue, lavender, and angelskin.
Red coral is referred to as precious coral. The most valuable coral falls within the red to pink color range.
Angelskin coral is nearly white in color, with a hint of pink or peach. Angelskin coral is the next most valuable color of coral, behind precious reds and pinks.
Black coral (or very dark brown) also occurs naturally, and is actually the official state gem of Hawaii.