The balls, which are often called "envelopes", were sealed and contain tokens in a variety of geometric shapes - the balls varying from golf ball-size to baseball-size.
High-resolution CT scans and 3D modeling were used by the researchers to look inside more than 20 examples excavated at the site of Choga Mish, in western
The balls were created about 5,500 years ago when early cities were flourishing in Mesopotamia.
The scans showed that some of the balls featured tiny channels, 1-2 millimeters across, crisscrossing them.
The tokens in balls come in 14 different shapes, which included spheres, pyramids, ovoids, lenses and cones.
The researchers, however, were puzzled when the scans found one clay ball had tokens made of a low-density material, likely bitumen.
The tokens, in this case, had air bubbles around them, which suggested that they had been wrapped in cloth before they were put in the ball, the cloth may have disintegrated over time.
In addition, it seemed that a liquid, likely liquid bitumen, was poured over the tokens after being inserted into the balls. (ANI)
Most Popular Stories
- Slow Week Ahead of December FOMC Meeting
- Hispanics Seek to Grow School Board Members
- 'Knockout Game': Myth or Menace?
- U.S. Companies Eager for Iranian Business
- Questions Remain in Jenni Rivera's Death
- Bitcoin Used to Buy Tesla Car
- Entrepreneurs' Next Creation May Be New Laws
- Banks Fret as Volcker Vote Approaches
- Obama Delivers Speech at Mandela Memorial: Transcript
- Paul Walker Fans Pay Respects