Serenity in Sponge Coral: Gemstone Jewelry for Calm and Tranquility Sponge coral, a beautiful type of coral. Sponge coral's rich and dynamic varieties make it an incredible expansion to any jewelry collection, and it very well may be utilized to make a great many pieces, from sensitive Sponge Coral earrings to perplexing necklaces and bracelets. Whether you favor exemplary styles or more present-day plans, Sponge Coral jewelry is a flexible decision that adds class to any outfit.