Although there are many types of coral, there is just one that is used in the making of jewellery - precious coral (scientifically known as Corallium rubrum)  Similar in shape to small leafless bushes, they grow to a height of around a metre.  The hard skeleton of the branches is naturally matte, but can be polished to give a glossy finish.  It exhibits a range of colours from pale pink to deep red - giving these colours the name of 'coral'.  

Owing to its intense and permanent coloration and glossiness, precious coral skeletons have been harvested since antiquity for decorative use.  Coral jewellery has been found in ancient Egyptian and prehistoric European burials, and it was especially popular during Victorian times.

These corals grow on the rocky sea bottom, usually in dark environments (crevices or caves) and are often found in the Mediterranean Sea.  There are several sites across the world that are famous for harvesting Coral.  These include the 'Coral Riviera' of Alghero in Sardinia; the Atlantic sites near the Strait of Gibraltar, at the Cape Verde Islands and off the coast of Southern Portugal.  There are also sites in the Pacific, notably near Japan and Taiwan.

The Romans believed that Coral could protect children from harm, as well as diagnose disease by changing colour.  In Hindu astrology red coral is associated with the planet Mars or Graha-Mangala and is used for pleasing Mars.