Salt is harvested from briny ocean water and underground deposits

The ocean gets its salt from runoff carrying fragments of eroded rock and from seawater dissolving salts and minerals from magma at seafloor spreading centers.

Desalination involves costly, energy-intensive methods for producing freshwater

Thermal desalination heats saltwater to produce steam, and reverse osmosis forces saltwater through a membrane that only allows water through. In both cases, freshwater is collected and remineralized for consumption, while wastewater brine is often returned to the ocean, where it may harm marine organisms.

Distinguishing the three types of mineral deposits collected via deep-sea mining

The greatest interest is in polymetallic nodules—structures formed from metals in seawater collecting around a core of shell, bone, or rock. Cobalt-rich ferromanganese crusts cover underwater mountain ranges and form over millions of years of metal deposition. Polymetallic sulfide deposits accumulate when seawater seeps into volcanic rocks.

Scientists have collected critical minerals from ocean water using seaweed, a type of algae that leaves behind a mineral-rich powder called bio-ore after being processed into biofuels.

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.

Gulf nations produce about 40% of the world's desalinated water

According to a 2023 report, six Gulf states produced 1.9 trillion gallons of freshwater across more than 400 desalination plants along their coasts. These plants create water suitable for human consumption by boiling saltwater and collecting steam or using high-pressure pumps to push seawater through a filter that only allows water molecules through.

Although consuming saltwater can dehydrate and kill organisms, some fish survive by using specialized gills that leach excess salt from their bodies back into the surrounding water.

In osmotic power systems, the natural movement of water from regions of low to high salt concentration is used to generate electricity from pressurized water.

Weird ways critical minerals are being mined

Critical minerals like lithium, cobalt, and graphite are economically crucial non-fuel resources subject to supply chain risks. To diversify production, scientists developed odd ways to harvest them. This article breaks down the weirdest approaches, including extracting minerals from seawater using algae, phytomining plants, and asteroids.

Nearly all of China's construction sand is artificial

Roughly 50 billion tons of sand are used in construction every year, mostly extracted from oceans, beaches, and rivers. To avoid depleting natural sand deposits, China crushes rocks and used materials to create an artificial sand, which it uses in 80% of its construction projects.

How five of the world's most expensive salt and spices are made

Part of the charm of certain spices and salts is their exotic origin, hailing from difficult-to-access locales or hewn via special processes. That also explains why they can be so expensive. Dive into the businesses of producing and marketing five of the world's most expensive food additives with this engaging video.

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.

Explaining the engineering challenges of extracting metal-rich nodules from the seafloor

Proposed solutions for collecting these potato-shaped rocks involve lifting a slurry composed of them, organic debris, and water through several kilometers of flexible tubing to a ship on the surface, a process that is more difficult than pumping crude oil. One method would use compressed air, but this method is only 15% energy-efficient.

Geothermal power can reduce the dangerous mining of rare earth elements

Geothermal brines—mineral-rich underground fluids extracted for use in geothermal plants—contain small concentrations of REEs that can be recovered after energy generation. Although researchers suggest that this retrieval requires complex extraction methods at a significant scale to account for high flow rates, the chemical processes also occur in traditional REE processing.

It's called kosher salt because it works for curing kosher meat

Kosher foods align with Jewish religious customs based on scripture. While there is a type of salt that is kosher (most often, salts without iodine), the kosher salt you see around the US is actually big, flaky salts used in a kosher process of curing meats.

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.

Explaining deep-sea mining, including its economic benefits and potential biomedical risks

Extraction via machines sweeping the ocean floor would reduce child labor and human rights violations currently occurring in land-based operations that collect the minerals needed for modern-day electronics. However, these sweeps may kill undiscovered organisms that possess biologies from which antibiotics could be derived and destabilize deep-sea ecosystems.

Sand 'batteries' can store excess electricity from the power grid as thermal energy

Energy collected from solar or wind power is used to heat insulated silos full of sand to temperatures as high as 450 degrees Celsius (842 degrees Fahrenheit), which can be retained for long periods. These thermal energy storage systems can be designed to boil water and generate electricity when needed.

Explaining why salt should be used to season food early in the cooking process

Experiments involving the same dishes, with salt added at the start of cooking versus at the end, have been shown to yield drastically different taste outcomes because salt takes time to diffuse into foods, particularly vegetables, whose cells are surrounded by cellular membranes and walls. Salting at the end will produce a concentrated surface coating, rather than even seasoning.

Pearls form when a saltwater oyster or a freshwater mussel coats a parasite or other irritant that has entered its shell with concentric layers of calcium carbonate and organic protein.

Often considered the largest natural mirror on Earth, Bolivia's Salar de Uyuni is the world's largest salt flat—a desert formation covered in minerals.

Read a history of how oral rehydration solution was created

Experiments dating back to the 1940s eventually led to the creation and standardization of a mixture of sugar, salt, and clean water that is now widely used globally.

Rocks, crystals, and gemstones are all made of minerals—solids that form from natural processes, such as evaporated water leaving salt behind or lava rapidly cooling into a solid.

Silicon must be 99.9999999% pure to be used in creating microchips

After the mined quartz is processed in an electric-arc furnace to remove oxygen from the silica, it undergoes the Siemens process, where it is bathed in hydrochloric acid. The liquid produced in the reaction undergoes multiple distillations to produce ultra-pure silicon in the end.

Where does your glass come from?

Glass is created from silica sand, soda ash, and limestone. The more transparent you want your glass to be, the higher the purity you need from your silica—a rarity. Colorless, low-iron glass featured in skyscraper windows and Apple's cube-shaped showrooms has increased demand for such pure silica.

Explore the chemical compounds found in fireworks

Besides the various salts and metals used to produce fireworks colors, shells are also filled with gunpowder and oxidizers to help fuel and accelerate reactions. Chlorates help strengthen colors, while dextrin, a starch, helps hold mixtures together.

The abundance of raw materials may lead to sodium replacing lithium in batteries

Lower risks of thermal runaway, which can lead to fires and explosions, and less energy capacity loss at low temperatures support the shift. However, sodium's greater weight and lower energy density compared to lithium have made it best suited for stationary storage applications. (Some readers may experience a paywall.)

Earth's easily accessible surface water in rivers and lakes accounts for about 0.01% of all the water on Earth, but 70% of this surface water is used for agriculture.

Diatomite, a sedimentary rock used as a filtration material in beer, wine, swimming pool water, motor oil, and pharmaceuticals, is formed from the fossilized shells of diatoms, a type of algae.

What's the difference between an ocean, sea, and saltwater lake?

What are the seven seas, the five oceans, and why isn't the Dead Sea considered a sea? This overview provides definitions for each.

How are scientists turning deserts into farmland?

This article explores how engineers are using a liquid nanoclay solution to transform barren deserts into productive fruit farms, drawing inspiration from how clay particles carried by floodwaters in the Nile Delta used to improve the fertility of...

Japanese scientists have developed an eco-friendly plastic that naturally dissolves in hours, leaving behind molecules containing phosphorus and nitrogen, which fertilize soil.

Earth's first oceans may have been as much as 230 degrees Celsius (446 degrees Fahrenheit), with atmospheric pressure preventing them from boiling.

Learn how aquifers and wells provide the largest reserves of accessible freshwater on Earth

Roughly a third of Earth's freshwater is stored underground in aquifers—permeable and porous rock formations where water naturally flows from the Earth's surface and accumulates. About half of this groundwater is accessed through wells, a feat of engineering used for thousands of years.

Solar panel manufacturing begins with silicon extracted from sand

The silicon is purified and shaped into wafers less than 0.2 millimeters thick, coated and connected through a criss-cross pattern of narrow and wider metal, followed by multiple rounds of lamination before bonding to a weatherproof panel.

Surface ocean currents are primarily driven by wind, tides, and Earth's rotation, while deep-ocean currents are driven by differences in temperature and salt concentration.

Some invasive species' populations have been controlled by turning them into cash crops that can be harvested and sold to produce useful materials.

Geode formation begins with trapped gas bubbles in igneous or sedimentary rock

Over thousands or millions of years, water seeps into the cavity created by the bubble and deposits minerals, which slowly build and crystallize into quartz, agate, amethyst or other crystals.

Why everyone is racing to get rare earth minerals

Rare earth minerals are crucial for high-tech electronics and transitioning to new energy sources. China currently dominates rare earth processing capacity, but the US is seeking to increase its mineral production by using its geopolitical influence to strike international mineral agreements with nations like Ukraine.

Clean energy technologies are more mineral-intensive than burning fossil fuels

Solar panels use silver due to its high conductivity, hydropower plants use chromium in their steel alloys, and geothermal plants need titanium to withstand abundant heat and pressure. Lithium—used in energy storage—is expected to see over 500% increased demand from 2020 to 2025.

As of 2025, China has been awarded the most deep-sea mining contracts by the ISA

The International Seabed Authority—established by the 1982 United Nations Convention on the Law of the Sea—grants 15-year contracts for governments and private companies to legally search for minerals and test seabed mining technologies. China is already the global leader in the processing and refining of critical minerals.

Lithium-ion batteries are the standard for rechargeable devices

The costly setup of new mining operations and challenges with recycling amid growing demand have led researchers to search for alternatives, including sodium-ion, solid-state, and lithium-sulphur batteries, despite challenges with scalability.

Mining of rare earth elements risks leaking radioactive wastewater

The extraction and processing of REEs requires significant amounts of water, and poorly regulated projects can contaminate groundwater with acids and heavy metals. Toxic waste spills have paused work in several US mines since the 1980s, despite growing REE demand.

Fracking provides access to fossil fuel reserves locked in underground rock

Using a pressurized fluid mixture that is over 90% water, cracks are created in shale about 2 miles deep to release trapped oil and natural gas. The process uses an average of 3 to 6 million gallons of water per well, which can strain local water supplies.

Scientists define sea level as the elevation to which water would settle on Earth's surface, given the planet's gravitational field and rotation.

Volcanic activity can lead to the formation of fertile soils

Ejected rock can introduce key minerals found in fertilizers, including iron, magnesium, and potassium, to improve soil quality. Ash and basalt crystals can be easily absorbed into soils, infusing them with sulfur, oxygen, chlorine, phosphorus, calcium, and other critical elements.

View a map of the distribution of mineral resources on the seafloor

Polymetallic nodules are found in regions near the middle of the Pacific Ocean, along the eastern coast of South America, and along the western coast of Africa, while cobalt-rich crusts span significant portions of the Pacific tropics east of the Philippines. Polymetallic sulfide deposits occur at tectonic plate boundaries, including areas within national jurisdictions.

Oral rehydration solution was developed in the 1960s in response to cholera deaths.

The warmest waters in the ocean are found at hydrothermal vents—hot springs on the seafloor that discharge plumes of mineral-rich water.

Most of the critical mineral supply needed for US data centers is imported

The country with the most data centers relies on other nations for about 80% of the rare earth elements needed for magnetic materials in storage drives, 64% of the silver and 85% of the platinum it uses for electrical circuitry, and about half the aluminum and copper used in heat sinks that dissipate thermal energy from electronic components.