By Seyit Kurt
ISTANBUL (AA) - As governments and industries race to secure the critical minerals that power modern economies, attention is widening beyond traditional mines to less obvious sources. Among them are stretches of coastline where dense, dark sands accumulate over time.
Supply chains for minerals used in high-tech manufacturing, renewable energy and defense systems have become increasingly politicized and concentrated in a few regions. That has pushed countries to look for alternative deposits that could diversify supply and reduce vulnerability to export controls or geopolitical tensions.
One such source is mineral-rich black sands -- heavy-mineral deposits found along some beaches, river deltas and coastal dunes. Once seen as ordinary sediment, they are now drawing attention as a potential source of strategic raw materials.
- What are black sands?
Black sands are typically black to gray because they contain high concentrations of heavy minerals. Although they resemble normal beach sand in grain size, they are noticeably denser. When wet, they often show a faint metallic sheen.
They form over long periods through a combination of volcanic activity, erosion of mineral-rich rocks and sediment transport. Rivers, waves and wind gradually separate lighter particles from heavier ones, concentrating valuable minerals in certain stretches of coastline or river mouths.
These deposits can contain a range of industrially important minerals, including ilmenite, magnetite, zircon, monazite, garnet and rutile. They may also hold base metals such as iron and titanium, along with smaller quantities of rare earth elements and, in some cases, traces of gold, according to a review in Developments in Sedimentology.
Among these, magnetite and ilmenite play a particularly prominent role, contributing both to the sands’ dark coloration and to their distinct magnetic properties.
A study of black sands in Egypt’s Nile Delta, for example, found large concentrations of iron and titanium dioxide, alongside smaller amounts of zirconium-bearing minerals and rare earth-bearing materials.
- Why are they valuable?
The minerals found in black sands are used across a wide range of industries.
Titanium-bearing minerals such as ilmenite and rutile are used to produce titanium metal for aerospace components and other high-performance applications, according to the Journal of Cleaner Production. They are also processed into titanium dioxide, a widely used pigment found in paints, plastics, paper, toothpaste and emerging nanotechnologies.
Zircon is valued for its durability and extremely high melting point, which makes it useful in high-temperature industrial settings. It is also the main source of zirconium and hafnium, metals used in chemical processing equipment, specialized alloys and certain nuclear-related applications.
Zircon-based materials are also used in ceramics, electronics, precision casting and specialized aerospace components.
Research by Northwestern University highlights monazite as one of the key mineral sources of rare earth elements. These metals are essential for technologies such as electric motors, wind turbines, batteries and many electronic devices like phones or computers.
Monazite can also contain thorium and uranium, making some deposits commercially relevant for nuclear-related materials as well.
- Where are major deposits found?
The US Geological Survey notes that although detailed descriptions of many individual heavy-mineral sand deposits remain limited, such deposits are found on nearly every continent, with Antarctica as the only possible exception.
Australia is one of the world’s leading centers of mineral sands extraction, with large operations producing ilmenite, rutile and zircon for global markets. Deposits there stretch for miles across coastal plains and sedimentary basins.
Egypt has another of the world’s largest reserves, and has promoted its black sand reserves along the Mediterranean coast of the Nile Delta, where mineral-rich sediments have accumulated over thousands of years.
Authorities say the scale of the deposits could support production for up to 200 years.
Other deposits are reported in India, Sri Lanka, Philippines, Senegal, China and the US state of Florida. While the sands themselves are widespread, the ability to process them into usable materials is far more limited.
Separating valuable minerals from black sands requires specialized processing plants and heavy investment. In many countries, that part of the supply chain remains underdeveloped.
Some governments have begun pushing for domestic processing rather than exporting raw sands, arguing that unprocessed exports mean lost economic value.
In 2022, Egypt inaugurated a large black sand processing complex, said to be the first of its kind with the most advanced mining equipment, to produce higher-value materials for export.
In the Philippines, lawmakers have proposed restrictions on exporting raw black sand to encourage local processing. A later bill filed in 2025 seeks to ban mining on black sand beaches altogether.
- Environmental risks and illegal mining
The development of black sand resources raises environmental and social concerns, because many deposits sit in fragile coastal ecosystems.
Mining or dredging operations can disturb seabeds, increase sediment in the water and damage habitats for fish, mangroves and other marine life.
“Studies by environmental groups in areas with black sand mining showed that black sand mining operations contributed to the depletion of fisheries, erosion of land and severe flooding in coastal and riverside communities,” said Philippine politician Leila de Lima in an explanatory note supporting the proposed mining ban.
“It is even predicted that areas mined for magnetite or black sand could sink and be underwater within 30 to 70 years as rapid subsidence will highly expose the said areas to flooding and seasonal typhoon,” she added.
In Fiji, community groups have called for mining projects to be halted or reassessed, arguing that residents were not fully informed about potential impacts. Similar concerns have been raised in parts of Africa, where sand mining has been linked to coastal erosion and damage to beaches and farmland.
Rising demand for critical minerals has also attracted illegal extraction. In some regions, authorities report black sands being trafficked across borders as part of illicit mining networks, with weak regulation making the trade difficult to control.
The growing interest in black sands reflects a broader shift in the global resource landscape. As competition for critical minerals intensifies, countries are looking not only to new mines, but also to unconventional sources like black sands or deep-sea mining.
Black sands illustrate both the promise and the tension of that search. They can hold minerals essential to modern technology and energy systems, yet they are often found in environments where extraction is politically sensitive, environmentally risky or difficult to regulate.
What appears to be an abundant coastal resource may therefore prove far more complex to develop, shaped as much by politics, technology and environmental constraints as by geology.