This slice of an orbicule of Orbicular Granite, polished on one side, 119gms, 10.5x6cms,  8mm thick, $30.00. orb53
This geologically interesting rock comes from near Mount Magnet in Western Australia. The orbicules occur in a granodiorite matrix. They consist  of andesine, plagioclase, hornblende, and biotite, arranged radially around a core of plagioclase and or hornblende, or less commonly mafic schist.
You are buying a natural rock. What may be perceived as an imperfection is actually part of Mother Nature's creation.