Geology

What's the difference between moissanite and diamonds? And which of these brilliant stones wins out when it comes to the engagement ring competition?

By Mitch Ryan

It's known as the "Gateway to Hell" and while it might not actually get you there, what it will unleash if it keeps thawing could truly be hellish.

By Patrick J. Kiger

If you think the largest desert in the world is hot and sandy, think again. These 10 deserts spanning the globe are massive, but they're not all sunbaked.

By Mitch Ryan

Ash flows, deadly gases and vog are just a few of the other reasons why we all need to respect volcanoes.

By Brittany Brand

Native Americans have quarried red pipestone from the land that is now Pipestone National Monument for centuries. What makes this particular stone so sacred?

By Jennifer Walker-Journey

Scientists are concerned that the Thwaites Glacier is melting at a rapid pace, though some don't love the name "Doomsday Glacier." What does the rapid melt of this huge glacier mean for the future of our planet?

By Mark Mancini

It was the world's largest diamond when mined and today it's cut into nine gems that are all part of the British Crown Jewels. But since the death of Queen Elizabeth II, questions have emerged about its imperialist history.

By Dave Roos

Radiocarbon dating is a cornerstone of climate and archaeological sciences. But it could be threated as fossil fuel emissions negate the useful signal from atomic tests.

By Caroline Hasler

Arizona isn't all desert. Take Grand Falls, aka "Chocolate Falls." It is dry most of the year, but when it rains, this waterfall pours.

By Patty Rasmussen

Split as if by a laser, the Al Naslaa rock in Saudi Arabia's Tayma Oasis baffles scientists and amateur geologists alike. How did this perfect split happen?

By Laurie L. Dove

Trovants, found only in a small town in Romania, are stones that actually seem to move and grow. But are they alive?

By Jennifer Walker-Journey

The element lithium is one of just three created during the Big Bang and has been used for mental health care for decades. But now it's in higher demand than ever before.

By Allison Troutner

Cinnabar's bright-red pigment has been used in jewelry, pottery and makeup for millennia. But cinnabar is also the primary ore for mercury, making it a dangerous mineral if the particles are inhaled.

By Allison Troutner

The rose-red mineral rhodonite was first discovered in the 1790s in the Ural Mountains of Russia. Today it's found globally and is associated with compassion, love and healing.

By Allison Troutner

Mountains might look like they're stoic and still, but research shows otherwise. Massive ones, like the Matterhorn, are moving all the time, gently swaying back and forth every few seconds.

By Richard J. Sima

Waterfalls are mainly reliant on precipitation to keep flowing. Here are six famous waterfalls that slowed to a trickle when drought set in.

By Laurie L. Dove

Nutty Putty Cave, near Salt Lake City, Utah, was discovered in 1960 and sealed up forever in 2009. But why?

By Dave Roos

This beautiful pink quartz is found in numerous places throughout the world and is thought to be associated with unconditional love.

By Carrie Whitney, Ph.D.

Not all diamonds are found on dry land. Many turn up in sediments below the ocean's surface. You just have to know where to look.

By Mark Mancini

Not all deserts have sand and they're certainly not all hot. They're just extremely dry and have little vegetation. That means deserts are located all over the planet, including at super-high elevations.

By Sharise Cunningham

The Mohs hardness scale is used by geologists and gemologists as a way to help identify minerals using a hardness test. How does it work?

By Carrie Whitney, Ph.D.

This ancient rock, which forms above copper deposits, is beloved for its swirling patterns and vibrant green color. It's dazzled humans for millennia as jewelry and even in décor.

By Carrie Whitney, Ph.D.

Tanzanite is so rare, it is sourced from just 8 square miles in Africa. It was first discovered in the late 1960s and it burst onto the jewelry scene thanks to Tiffany & Co.

By Carrie Whitney, Ph.D.

There are caves all over the world, but some are in places that are hard to explore — hidden by rocks, ruins or even under ice. We've found seven secret caves you probably never knew existed.

By Stephanie Parker

This ancient rock adorns King Tut's coffin and the Sistine Chapel. And at one time it was more precious than gold. What is it about this deep blue rock that has drawn us in for centuries?

By Carrie Whitney, Ph.D.