Grade A Blue Coral Gold Plated Magnetic Clasp Necklace. Blue Colour Coral is a rare kind . Blue Coral are on the IUCN 'vulnerable' list – which means they are close to endangered, but not quite there yet. *Blue Coral is also called the stone of harmony and growth. It's also known as the named Sea Gardens because of just they look like as a plant. If people interact with ocean energy while this stone carries, people will gain protection from evils and negative energies.