The eggs used with this game are made of fossiliferous limesone from the Las Belas area of Baluchistan that is turned on lathes in Karachi, Pakistan. These marine fossils, 30 million years old, lived in the Tethys Sea between the colliding Sub-Continent of Pakistan-India and Asia. The matrix that cements the fossils together is fragments of other fossils broken up in the surf prior to its lithification into limestone. The circular fossils with internal radiating dividers are coral. The chambered fossils are snails. The arcuate fossils are cross-sections of clams.
information via Larry McMaster MS, geologist Bowling Green State University, Ohio USA