We have all heard the story of a professor who took rocks, pebbles, gravel, sand and water and asked students what order was needed to fit it into the jar.

In the nearly 50 years since Apollo 11 astronauts first landed on the moon, the more than 842 pounds of rocks, pebbles, sand and dust collected during U.S. moon landings have been variously stolen ...

There's no sand on these beaches – instead, rocks and pebbles dot the spectacular views When we think of a beautiful beach, the usual image is of powder-fine white sand and clear waters ...