The stone spheres of Costa Rica, one of the strangest mysteries in archaeology, are a collection of some three hundred polished stone orbs, the first of which were discovered in the Diquis Delta of Costa Rica during the 1930s. The spheres range in size from a few centimeters to over two meters in diameter, and weigh up to 16 tons. Their precise date of construction is uncertain, but they are believed to have been carved between 200 BC and 1600 CE.
The stone spheres came to light during early cultivation of the farmland. Most were discovered by workmen as they cleared and burned the jungle in preparation for planting.
The first scientific investigation of the spheres was undertaken shortly after their discovery by Doris Stone, a daughter of a United Fruit Co. executive. These were published in 1943 in American Antiquity, attracting the attention of Dr. Samuel Lothrop from Harvard University. Lothrop’s findings were published in Archaeology of the Diquís Delta, Costa Rica 1963.
Numerous myths surround the stones, such as they came from Atlantis, or that they were made as such by nature. Some local legends state that the native inhabitants had access to a potion able to soften the rock. Another calls for the center of the spheres to contain a single coffee bean.
The stones have a surprisingly smooth surface. According to laser measurements by researchers from the University of Pennsylvania, the spheres were 96% perfect.
The stone spheres have been found in clusters of up to twenty, and often in geometric patterns such as triangles, rectangles or straight lines. Such alignments often point to the earth’s magnetic north. Archaeologists have been able to date the stones by the artifacts that have been found lying alongside them. Some of them have, thus, been dated as far back as 400 B.C.E.