"Even after melting, the stone [produced from the thunderstorm that struck Vivian, South Dakota, U.S. of A., on 23 July 2010] still measured 8.0 inches in diameter and weighed nearly 2 pounds (1 pound, 15 ounces) with a circumference of 18.62 inches." Photo credit: National Oceanic and Atmospheric Administration (NOAA)
Source:
http://www.noaa.gov/features/02_monitoring/images/hail2.jpg
