Archaeologist Susumu Morimoto recently made a landmark discovery that could change today's views of Japan's ancient measuring system and of the Yayoi Period (300 B.C. to 300).

The head of the International Cooperation Section at the Nara National Research Institute for Cultural Properties discovered that what were believed to be grinding stones from the first half of Yayoi, about 2,400 years ago, are actually weights for scales.

"This would be my first and last discovery, and the greatest (in my life as a researcher)," Morimoto, 54, said.