I assume many of you have already heard about "Las Bolas" or stone spheres (balls) of Costa Rica. So did I. Contemporary explorers suggest that those spheres, many of which weigh more than 10 tonnes, might have been used for astronomical observations or as status symbols. Some other put forward more wild theories, involving UFOs or the legendary continent of Atlantis.
Nonetheless, even after I'd started to publish my reviews of business climate for SME around the world, and wrote an article about this country where those gigantic petrosphere are found in such abundance, I haven't really given them any second thought and just classified those curious megalithic artefacts as another "touristic attraction".
I'm economist by training - not an archeologist or an ufologist and my professional curiosity haven't been really engaged by those big round rocks until I stumbled on the description of the heavy limestone discs (Rai), which are used by inhabitants of the island state of Yap as money.
The idea is very simply. Say, buying, a pig with one Rai involves orally agreeing that the ownership has changed. You can't really steal a 4-tonnes piece of aragonite and calcite crystals packed together. Well, not without special equipment.
Therefore, I assume, those "Las Bolas" might also be money.
They are very difficult (although not absolutely impossible even with primitive tools) to produce. Hence, counterfeiting or inflating that type of currency is not really an option.
They are very heavy but because of their spherical form they can be rolled by a group people for a short distance to form a various geometrical arrangements, which might represent different sum of money if necessary.
And, of course, you do not need to guard them and they do not rote, can't be burned or even really damaged.
Actually, I've thought that this must be one of the most naturally occurring hypothesis among scientists. However, to my astonishment, Google search doesn't produce any of the kind.
So, I decided to write this article. Just to fill the void.