Paleontologists have confirmed that a rock enclosing a perfectly round agate crystal is actually a titanosaur egg, which was probably smothered by lava after a volcanic eruption 67 million years ago.

NASA's Curiosity rover revealed an 'oasis' of rare elemental sulfur on Mars after accidentally crushing a rock with its tires. The yellow crystals have never been spotted on the Red Planet before.

The moon’s surface formed at least 40 million years earlier than previously thought, according to a new study of an ancient crystal embedded in rock collected by Apollo 17 astronauts. For years, ...