The 600-year-old coin found in a Kenyan island of Manda reveals new history.

The Field Museum in Chicago announced the find Wednesday.

The rare Chinese coin was found by scientists from Illinois suggest that there may have been more trade between Africa and China before the arrival of Europeans than previously known.

The expedition was led by Chapurukha Kusimba of the museum and Sloan Williams of the Univeristy of Illinois-Chicago as well as scientists from Kenya, Pennsylvania, and Ohio.

The very small coin itself is made of copper and silver, bearing a square hole in the center. They were called "Yongle Tongbao" after the Dynasty Emperor of the time, Emperor Yongle. He ruled between 1403 and 1425 in China. He was known for sending Chinese explorers, including the famed admiral Zheng He, to explore around the Indian Ocean.

"Zheng He was, in many ways, the Christopher Columbus of China," said Dr. Chapurukha M. Kusimba, the curator of African Anthropology at The Field Museum. "It's wonderful to have a coin that may ultimately prove he came to Kenya."

Kusimba said that "Chinese currency in East Africa is very, very rare."

"Whether it turns out to be fake it is still extremely exciting. It speaks to the competition going on between merchants, the kind of competition that is still visible today," he told the Chicago Sun-Times.

Researchers during the major expedition to the island of Manda, where the coin was originally discovered, even managed to find human remains and other artifacts that were even older than the coin.

"We hope this and future expeditions to Manda will play a crucial role in showing how market-based exchange and urban-centered political economies arise and how they can be studied through biological, linguistic, and historical methodologies," Kusimba concluded.