I drove past this house wandering around in central Tucson the other day. Wow, sure wouldn't want to run into these bees! *smile* Looks like huge pieces of honeycomb, but of stone.
I have no idea what or where or why the holes were created. My guess is that someone has a really boring job -- you know, same old drill at work every day; other employees with a holier than thou attitude; loud rock music in the background all day; trying to stay focused on the light at the end of the tunnel.
Seriously though, my best guess, and only a guess, is that maybe these are from boring out round blanks that are then cut sideways into round coasters like I sometimes see in stores?
Anyone have any ideas?