Gogottes are naturally occurring sculptures found in Fontainbleau, France, the one time home of the French monarchy. They date back to the Oligocene Period, 30 million years ago and are made of quartz crystals and calcium carbonate.
Gogottes are formed when superheated water extrudes through crevices into a basin of extremely fine white silicate sand. The water is then saturated with calcium carbonate (limestone), and their swirls and eddies are captured in the gradually concreting stones, forming one-of-a-kind sculptures.
One specimen was acquired by the Smithsonian Institute in Washington and so prized that it remains on display right next to the Hope diamond.