Coral (Black)
About Coral (Black)
Not a mineral but the skeleton of a marine animal - black coral is the state gem of Hawaii. It can live for 4,000+ years, making it one of the oldest living organisms. Unlike reef-building corals, black corals lack symbiotic algae and live in deep water. It has been harvested for jewelry for 5,000 years. The polish reveals a brownish-black color with golden luster. Overharvesting has depleted many populations. It is now protected in many countries. It grows only 3-30 micrometers per year. Hawaiian black coral jewelry is highly valued. International trade is regulated by CITES.
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