The mysterious qualities of obsidian and magnetite

Magnetic material in rocks provides evidence of flips in Earth's magnetic field

Volcanic rocks can lock in the direction of Earth's magnetic field as they cool, making them natural recorders of magnetism. Dating rocks and seeing the changing orientation of their magnetic field helps construct a timeline of Earth's magnetic field history.

In 2009, accidentally drilling into magma provided time capsules of volcanic glass

While drilling for geothermal energy in Iceland's Krafla Geothermal Field, magma encountered at a depth of 2,100 meters quickly formed glass upon making contact with drilling fluid. By trapping dissolved gases, volatile chemicals, and the physical characteristics of magma before cooling, the glass acts as a time capsule of ancient volcanic activity and magmatic conditions.

When did people start making and using glass?

This article details the search for the ancient origins of glass, a now-common item through which archaeologists can spot histories of trade and innovation. Bronze Age glass was made from crushed quartz instead of sand, and artisans could color glass with materials such as cobalt. These trace metallic add-ons have given scientists a vital clue into the origins of glass, which is currently debated as either Egypt or the Near East.

Minerals, crystals, rocks, and gems explained

Have you ever wondered what differentiates a mineral from a rock or a crystal from a gem? This three-minute video from the American Museum of Natural History elaborates on the unique properties and compositions that separate minerals, rocks,...

The medieval meaning of your birthstone

Medieval people viewed birthstones very differently from modern jewelry marketing. Rather than simply being decorative, gems were believed to possess extraordinary magical, medical, and mystical powers. This article breaks down some fascinating insights into medieval gemstone beliefs, including that diamonds could fend off insanity and nightmares.

The chemistry of ancient tacos

This 16-minute podcast explores the chemistry of Mesoamerica's corn tortillas, which involve a 3,500-year-old chemical process called nixtamalization that releases vitamins, including niacin, one of the essential B vitamins. This process also makes the tortillas softer and more delicious. Corn tortillas were a staple in Mesoamerica, and the archaeologist interviewed in this podcast argues cultures like the Aztecs and Maya wouldn't have thrived without nixtamalization.

The iconic Aztec 'crystal skulls' were 19th-century fakes

The crystal skulls long displayed as Aztec artifacts were actually fabricated in the late 1800s, all linked to French antiquities dealer Eugène Boban. Anthropologist Jane Walsh's investigation exposed their modern origins, overturning a century of mistaken museum lore.

Some 19th century astronomers thought Mars was inhabited

As telescope technology advanced, astronomers became able to observe the surfaces of objects in our solar system with greater detail. The dips, valleys, and lines crisscrossing Mars, particularly, captured onlookers' imagination, leading some to speculate that the seemingly organized features could only have been created by an intelligent civilization.

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

An overview of the metals obtainable through deep-sea mining of nodules and crusts

Polymetallic nodules are a source of manganese, cobalt, nickel, copper, molybdenum, and platinum, which are used in batteries, fuel cells, and metal alloys of electric vehicles. Seamount crusts contain rare-earth elements deemed essential to US national and economic security, including neodymium and dysprosium used to make permanent magnets.

Humans were forced to adapt to survive a supervolcano eruption 74,000 years ago

The Toba supereruption ejected 2800 cubic kilometers of ash, resulting in global cooling from blocked sunlight and acid rain. Archaeological sites show that humans developed bow-and-arrow technology to survive in arid conditions by fishing in seasonal waterholes.

The Aztecs worshipped Mictecacihuatl, goddess of the underworld

Some elements from ancient festivals honoring Mictecacihuatl and other deities, like incense, skeleton imagery and marigolds, have been incorporated into modern Day of the Dead celebrations, possibly indicating that the holiday blends indigenous and Catholic traditions.

The unsolved mysteries of Machu Picchu

Who lived there? How did they get all that granite up there? Who were the 100 bodies found buried here, and why did some of them have elongated heads? Explore eight of Machu Picchu’s unanswered questions while scrolling through panoramic, clickable street-view images of the site, in this guide from Google Arts and Culture.

Mezcal is a handcrafted spirit made by Indigenous producers in Oaxaca

Unlike tequila, mezcal can be made from dozens of agave varieties and is traditionally produced by small-scale families in Oaxaca using stone pits and clay pots. The spirit's rising popularity in US bars has brought both economic opportunity to producing communities.

The centuries-old history of titanium white goes back to the Inca

Titanium white can be found in items ranging from paint to pills. Though it was created in New York in 1908, the pigment was first used hundreds of years earlier by the Inca, according to this article.

Hypotheses on the origins of Earth's water, from comets and asteroids to magma oceans

Before Earth's atmosphere formed, any liquid water would have boiled off, preventing the accumulation of water early on to create today's oceans. Planetary scientists continue to debate whether this water was delivered later from comet or asteroid collisions or via reactions between iron oxide in Earth's molten surface and hydrogen gas from the planetary nebula.

A collection of ancient Mayan glyphs and pictographs

The Maya had a syllabic and pictorial writing style that featured many incredibly detailed glyphs. Click here to check out this ancient writing style (and maybe test out their related phonetic sounds).

Layers of minerals revealed by erosion give Vinicunca its distinct colorations

Located in Peru's Andean mountains, Rainbow Mountain is known for its vibrant colors, which result from layers of minerals such as clay, sandstone, argillite, and limonite exposed over millions of years by rain, snowfall, and strong winds.

Volcanic ash is composed of fragments of volcanic rock, minerals, and glass

These abrasive particles are hazardous to aircraft. They can melt within engines and re-solidify on turbine blades, preventing forward propulsion. If inhaled, chemicals within ash can be toxic, and the particles can embed themselves into the lungs' ducts, causing suffocation.

O’Keeffe collected animal skulls and bones for her art

O’Keeffe used bones as motifs in her work throughout her time in New Mexico. She famously stated, “The bones do not symbolize death to me. They are shapes that I enjoy … They're very lively.”

Blood evolved many times over hundreds of millions of years

The earliest evidence of a blood-like substance comes from ancient arthropods, which appear to have had copper-based blood. In the 500 million years since then, some creatures have grown to rely on other variants, such as humanity's iron-based blood.

Hacking the body for a future that didn't happen

Journalist Adi Robertson experimented with one of the most accessible biohacks: magnets. Having a tiny magnet in their right ring finger meant they could sense magnetic fields, attract small metal objects, and more. But magnets weaken over time, eroding this new sense. Such implants do more than offer a new way of interacting with the world, they also pose new complications, such as the inability to get an MRI.

Auroral myths include Valkyries, firefoxes, and torchlight from giants fishing at night

In Norse mythology, the light displays were considered reflections from the Valkyries' armor as the female warriors brought the souls of heroes to Valhalla. In Finland, firefoxes were thought to move so fast that they created sparks in the sky as their tails brushed against mountains.

The medieval origins of Māori and Moriori culture

New Zealand, also known as Aotearoa, was one of the last large land masses inhabited by humans. This 18-minute video explores the ancient origins of Polynesian people and their medieval journey to New Zealand and the nearby Chatham Islands archipelago.

Tracking the latest meteorite falls on Earth

Roughly 50 tons of meteorite material arrives on Earth every day, and many of the larger objects survive the hot temperatures of the atmosphere and make landfall. This tracker compiles data from survey sites across the globe to present the latest...

Tombaroli steal precious items from ancient people's tombs in central Italy

The tombaroli, or tomb-robbers, raid ancient Etruscan tombs in the dark hours of the night to recover vases, statuettes, mirrors, ornaments, jewellery, and other objects in gold, bronze, and terracotta. Read a firsthand account of a tombarolo who made a living handing stolen items to middlemen who sold them to wealthy buyers abroad. The lives and practices of tombaroli are also explored in the 2023 film "La Chimera."

The deadliest aspect of volcanic eruptions is often not lava, but pyroclastic flows—avalanches of ash, gas, and rock that can move more than half the speed of sound.

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

The first robot in literature may have been a 'mechanical man' in 1907's 'Ozma of Oz,' a book in L Frank Baum's 'Wizard of Oz' series.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

See photos of Meteora, a mountainous site in central Greece, home to 14th-century monasteries perched atop soaring outcroppings.

Exploring the Larry Bird punch that almost changed March Madness

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

Browse a detailed visual analysis of over 200,000 similes—comparisons that often use 'like' or 'as'—from popular fiction to see how frequently writers the same idiomatic expressions.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

Scientists have struggled to pin down Ebola's natural reservoir species for decades, but the available evidence suggests that it's very likely fruit and insect-eating bats found in Africa.

Georgia O'Keeffe's flower paintings are often assumed to be sexual, though the artist claimed she was simply interested in highlighting the beauty of flowers that most people neglect

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

The word 'jazz' evolved from 'jasm,' 19th-century American slang for 'energy'

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

Some researchers have labeled nomophobia, the fear of being without your phone, as 'the phobia of the 21st century.'