Diamond Head, Oahu, Hawaii is the name of a volcanic tuff cone on the Hawaiian island of O'ahu. Its English name was given by British sailors in the century, who mistook calcite crystals on the adjacent beach for diamonds. Hawaii is the state.
Ball Pyramid - the world’s tallest sea stack. It is the remains of a shield volcano formed about 7 million years ago, located southeast of Lord Howe Island in the Pacific Ocean. Ball's Pyramid is part of the Lord Howe Island Marine Park in Australia.