Odd balls. The moqui marbles' precise ages come from a radioactive clock. The iron oxide minerals contain traces of radioactive uranium and thorium, and these decay by expelling helium.

The sandy landscapes of southern Utah are home to a bizarre geological phenomenon. Brown-black balls ranging in size from a pea to a grapefruit litter the deserts of the Beehive State (and other ...

Where the Navajo Sandstone loses its iconic peach, orange and red stripes, hundreds of round, iron-coated stones often litter the ground. The stony spheres are concretions — sandstone balls cemented ...

Moqui marbles on a sandstone slope. A new study reveals that the moqui marbles are less than 25 million years old. Millions of years in the past, a mixture of water and natural gas flowed through ...

And, for that matter, what are Moquis? Continue reading → Some states pose more mascot questions than they answer. Case in point: Why does Escalante (Utah) High play as the Moquis?

The balls are commonly found in the US but similar structures have been discovered in other parts of the world, such as Mongolia. Perhaps most excitingly, these marble-like objects have also been ...