Stone Balls have been discovered all over the world. The ones located in Costa Rica are the subject of many books and some of the authors misrepresented themselves as the ones who discovered them. However, they were actually found in 1940 during agricultural activities by the United Fruit Company. They were clearing land Diquis Delta to be used for banana plantations. An archaeological investigation was underway shortly afterward along with the first scholarly publication about them appearing in 1943.
Hundreds of these balls have been documented all over the country of Costa Rica. Although some have been destroyed, dynamited by treasure hunters or cracked and broken by agricultural activities. Only six are believed to be in their original locations. They range from a few centimeters to over two meters in diameter. Almost all of them are made of granodiorite, a hard, volcanic stone, possibly taken from a Talamanca mountain range about 50 miles from their location. Unlike the stone balls in Jalisco, Mexico, they are not natural in origins but monolithic sculptures made by human hands.
No one knows exactly how old they are. Costa Rica has no recorded history before 1502 when Columbus made his fourth transatlantic voyage. Archaeologists used pottery and other artifacts found near the balls to make their best educated guess. They believe the balls could have been made anywhere between A.D. 200 and 1500. Old but not as old as the pyramids or Stonehenge.
How or why they were created remains a mystery.