Black septarian, also known as dragon stone, is a unique sedimentary rock composed of a combination of minerals including calcite, aragonite, and limestone. It is typically black or dark brown in color with distinctive yellow, white, or brown patterns caused by the presence of these minerals. Black septarian is believed to have formed around 50 million years ago during the Cretaceous period and is found in various locations around the world, including the United States, Madagascar, and Australia. It is often used for decorative purposes in jewelry, sculptures, and other ornamental objects.
