Coral is an ancient gemstone that has been used since ages. Coral organisms are called polyps. These polyps are small and soft marine organisms. Each of these small marine animals uses calcium carbonate from seawater to build homes around themselves. On death of a polyp, another polyp builds a house over it and the formations increase with the death of each polyp. These increased formations are called coral reefs. Coral reefs are very ancient and they have been on earth for more than 200 million years. And they enjoy the status of being the most massive structure ever created by group of animals all over the world.
Types Of Coral Reefs
Coral reefs house over thousands of species and around 25 percent of them are well known such as fish, coral and various other plants and animals. Coral reefs are of different types out of which three are more popular and they are fringing reefs, barrier reefs and atolls. The most commonly seen type of coral reef is fringing reef. These reefs are closer to the shore and in most cases, a shallow lagoon is found between the main reef and the beach. Barrier reefs are found away from the land. Barrier reefs are bigger sized than fringing reefs. Atolls are circular or oval in shape and they are formed when a volcanic island sinks under the water in which coral reefs are developed. After the island completely submerges, the coral reef on the island remains and retains the shape of the land to an extent.
Coral colonies are found in different shapes. The shapes are determined by the environment in which they grow and the species they support. Where the wave action is stronger, corals are round in shape and smooth on the surface. In waters that are calmer and deeper, you will find branched corals that are delicate.
Colors Of Corals
The bodies of coral polyps are mostly clear with white skeletons. Coral reefs support tiny algae known as zooxanthellae and these algae contribute to the colors of corals. A square inch of coral consists of several millions of these algae, which produce pigments. The clear bodies of coral polyps make the presence of these pigments visible. Hence, they are seen in various colors, which include red, pink, orange, black, blue and white.
Red coral has been around for centuries and this is the most popular of all coral colors. Red coral or orange coral, being found naturally is now rare as the rate of harvesting is higher than its growth.
Pink coral is nothing but the faded red coral. It is available in great numbers and it has its own attraction. Black coral is very rarely found and it is one of the most beautiful coral colors. Blue corals are unlike other coral colors and they thrive in circumstances where other colored corals would not survive.
Though you find just a few colors mentioned, natural corals are found in a wide range of colors. Discoloration of corals results in increased numbers of colors. Apart from being found in natural colors, corals are dyed to produce different colors. The price of the corals depends on their quality, color and availability.