When I was on vacation in Costa Rica, I kept my eyes open for cool or interesting things. A few days before the end of my trip, a tourist at an internet café asked me if I knew about the “stone .” At first, I thought he was trying to sell me drugs, but, he continued to tell me about the balls: “There are these mysterious stone balls that are perfectly round. So perfect in fact, that there is no way they were carved by hand. No one knows where they came from, and no one knows what they are for. The natives like to use them as lawn ornaments.” Bewildered, I kept my eye out for these stone spheres, these Costa Rican lawn gnomes, and I did indeed spot a few. The ones I saw ranged from a dozen centimeters across, all the way up to a meter in diameter, and they really look like perfect spheres.

The unusual spheres were first discovered around 1940. The United Fruit Company was clearing large tracts of land in the Diquis Delta to be used for banana plantations. In the process of clearing the land, they unearthed several dozen spheres, ranging in size from a few centimeters to over two meters in diameter. Archeological research identified and catalogued hundreds of the spheres, some of which appeared in other parts of the country. Due to their popularity, many of the spheres were removed from their original sites by treasure hunters, and sold to collectors, or gathered up by the locals for use as decoration.

Columbus’s fourth arrival to Costa Rica marked the introduction of written history, and there are no records of the spheres before 1502. Educated guesses have been made by dating artifacts found around the spheres. Best estimates place the spheres construction between 850 and 1150 AD, so they are old, but not that old.

The spheres are made of Grandiorite, a hard volcanic stone; however, several limestone variants have been found. The quarry from which the Granodiorite came from has been narrowed down to the Talamanca mountain range, which is eighty kilometers from the sphere's current resting place. Presumably the spheres were carved there, to facilitate transportation. Some of the larger spheres measure three meters in diameter and would have been near impossible to transport before they were shaped..

Ancient cultures all over the world have been carving stone into complex statues for centuries, however according to some accounts, the spheres are too perfectly round to have been carved by even modern machinery. These claims are usually based on parts of stones, and do not take into account weathering and erosion. Geologists note that if you heat Granodiorite, and then cool it quickly, it turns to a thin layer of flakey stone which can be knocked off quite easily. It’s not beyond reason to assume that ancient stone carvers could have heated the stone with coals, and then cooled it with water, and shaped the stone using this method.

The real mystery, and it’s a big one, is why these extraordinary sculptures were created. Many reasons have been put forward, and range anywhere from use as markers or signposts, to part of an alien power grid. Many believe they may have had an important part in religious figures. I particularly like the idea that they were created to be what they are used for today, garden ornaments, they were created as giant status symbols.

Unfortunately, most of the spheres have been damaged by agricultural machinery and moved from their original locations. Some were even destroyed when a rumor went around that they were filled with gold. There isn’t much interest in these spheres by the academic community so it is likely that they will forever remain a mystery.

Pictures of the spheres can be found here: http://www.geocities.com/eqm/palmar/palmar.html

- Hoopes, John W. Debunking the "Mystery" of the Stone Balls. 2000. 12 Mar. 2005 {http://www.ku.edu~hoopes/balls/}.
- Quesada, Edwin. Stone Balls from Costa Rica. 1999. 12 Mar. 2005 {http://www.geocities.com/eqm/palmar/palmar.html}.