Like a lover's heart , beach stones may at first seem free of imperfections. Years of continual tumbling and scouring by surf and sand have rounded off any rough edges. But a closer inspection reveals miniature cracks, pits and rough spots. With a commitment of time, these almost invisible surface features can be used to entice even the largest boulder to a point of blissful equilibrium.This precariously balanced stone, about 20 in (50 cm) across and weighing approximately 40 pounds (19 kg), was one of a group of balanced rocks that the photographer was surprised to encounter late one afternoon while exploring the tide pools at Dana Point Marine Life Refuge , on the coast of Southern California. This impromptu art gallery , created by a local lover of nature, was doomed to be only a brief affair; within a few hours all were brought back to earth by the forces of gravity and the rising tide . Photo taken on December 27, 2008.