What's sponge coral jewelry

Over the years lots of new jewels has appeared on the jewelry market, and sponge coral jewelry is one of them. From its name we can learn that it belongs to coral family. But why it is called sponge coral? What is special of this kind of coral jewelry? In this passage, we will offer a general introduction to the sponge coral jewelry.
Sponge coral jewelry is made of sponge corals. Sponge coral is not sponge at all. In fact it is the sponge-like appearance of the coral earns it this name. Like other corals, sponge coral is formed by polyps that create housings for themselves made of calcium carbonate. But unlike other corals, sponge coral is filled with holes, for this kind of polyps don’t close the coral structure entirely. Those holes give sponge coral a sponge-like appearance.
The feature of sponge coral is its vibrant orange-red color. Some corals have yellow streaks or tinges in it; some have a brownish tint or large yellow area, which is regarded as low in quality. Though those in quality are not valuable, their unique patterns make them popular in jewelry making.
When the sponge corals are first harvested, they are usually soft and rough, and have to go through some treatment before being used in making jewelry. Most sponge coral jewelry found on the market has been stabilized. Some sponge coral has been dyed to enhance its natural color.
Different people have different taste to jewelry. If you have a special passion for coral jewelry, you may want to try the beautiful sponge coral jewelry.