Introduction to the piebald colored stone: The piebald colored stone is a rectangular sea stack with a total volume of 7,000 cubic meters. It is a basic volcanic rock-tuff that was erupted by the Cambrian volcano and is 500 million years old. It has been hailed as a scenic spot in Dadong since ancient times. In recent years, it has been hailed as "the most amazing stone in the sea of ​​China". It is located in Lianluo Bay, Madao Town, northeast of Rongcheng City.