PERFECT ORBS OF EARTH
How can a machine transform rough mineral samples into beautiful objects of art? It takes a few more steps than pushing buttons. First, the lapidary must determine if the stone is sufficiently stable for carving, noting any flaws or other features that could complicate the process. Using a masonry or rock saw, the stone is then cut into a cube shape. Depending on size, 12-16 more cuts reduce the specimen to a sphere-like geometric shape. Cutting the stone down first not only reduces the work the machine has to do, but also makes it capable of spinning within the machine. Sphere cutters typically have 2 to 3 cup-shaped polishing pads which round off the remaining corners. In order to get a perfect sphere, the stone must be able to spin at random between these pads. Depending on the hardness of the rock, in several hours the stone will be round and ready for polishing.