A temporary limit on imports, from all countries, to protect a local industry from a sudden surge.
Unlike anti-dumping duties, safeguards don't require proof of unfair trade, only that rising imports are seriously hurting local producers. They often take the form of a quota, with a tariff charged on imports above it.
Example: The EU applies a definitive safeguard measure to imports of certain ferroalloys.
Where you’ll see this: 5 material pages
Related: Tariff, Anti-dumping and countervailing duties, Ferroalloy
Penalties that limit trade or payments with a country, company or person, usually for political reasons.
Sanctions can block imports from a producer, ban dealing with certain companies, or cut off access to banks. When a major producer is sanctioned, its material may still be sold, but only to some markets, which reshapes trade flows.
Where you’ll see this: 5 material pages
Related: Export control, Tariff
Used or leftover metal that is collected to be melted down and used again.
New scrap is the offcuts and rejects from factories; it is clean and easy to reuse. Old scrap comes from products at the end of their life, such as cars, cans or batteries, and needs more sorting.
Scrap has its own HS codes, so it shows up separately in trade data.
Where you’ll see this: 39 material pages
Related: Recycling, HS code
A US law that lets the President restrict imports that threaten national security.
Section 232 of the US Trade Expansion Act of 1962 starts with a Commerce Department investigation. It has been used for tariffs on steel and aluminium and for investigations into other critical minerals.
Where you’ll see this: 5 material pages
Related: Tariff, Critical mineral
A material that conducts electricity only under certain conditions; the basis of computer chips.
Silicon is the main semiconductor, but gallium (in gallium nitride and gallium arsenide), germanium and indium are used for fast, power-efficient and light-emitting chips. These metals are needed in very small amounts and at very high purity.
Where you’ll see this: 11 material pages
Related: Purity (4N, 5N…), Dopant, Photovoltaic
Pressing powder into a shape and heating it until the grains bond, without fully melting it.
Sintering is used to make parts from metals with very high melting points, such as tungsten, and to make cemented carbide tools and rare earth permanent magnets.
Where you’ll see this: 9 material pages
Related: Cemented carbide, Permanent magnet
The glassy waste that separates from molten metal during smelting.
When ore is melted, the unwanted rock forms a separate liquid layer called slag, which floats on the metal and is poured off. Materials added to help it form, such as limestone or fluorspar, are called fluxes.
Some slags are valuable. Tin slags can contain tantalum and niobium, and steel slags are a possible source of vanadium.
Where you’ll see this: 12 material pages
Related: Smelting, By-product
Heating ore or concentrate in a furnace until it melts, so the metal separates from the rest.
A smelter uses very high heat, and usually a chemical such as carbon, to pull metal out of its ore. The waste floats off as slag.
Smelting usually gives a rough metal that still needs refining. Smelters use a lot of energy, so they tend to be built where electricity is cheap and reliable.
Where you’ll see this: 27 material pages
Related: Refining, Arc furnace, Concentrate, Slag
A hard-rock mineral that is the main source of lithium outside the South American salt flats.
Spodumene is mined from rock, mostly in Australia, then concentrated and usually shipped to China to be converted into lithium carbonate or hydroxide. Its concentrate is often described by its lithium oxide content, such as "SC6" for about 6% Li₂O.
Where you’ll see this: 2 material pages
Related: Brine, Concentrate, Hydroxide
Metals, alloys & compounds A porous, crumbly form of metal straight from production, before it is melted into solid ingots.
Titanium, zirconium and hafnium leave the Kroll process as sponge. Some precious metals, such as iridium and platinum, are also sold as sponge. Sponge is then melted, often with scrap, to make ingots.
Where you’ll see this: 9 material pages
Related: Kroll process, Refining
Metals, alloys & compounds Steel with at least about 10.5% chromium, which forms a thin protective layer that stops rust.
Stainless steel is the biggest use of chromium and a major use of nickel and molybdenum. Most of its chromium comes from high-carbon ferrochrome.
Where you’ll see this: 9 material pages
Related: Ferroalloy, High-carbon and low-carbon grades, Corrosion resistance
Also called: National Defense Stockpile
A store of a material held by a government or company as insurance against supply disruptions.
Governments keep strategic stockpiles so that defence and key industries can keep running during a crisis. The US National Defense Stockpile is managed by the Defense Logistics Agency. Japan, South Korea and China also hold stockpiles, and the EU is setting up joint stockpiling.
Where you’ll see this: 21 material pages
Related: Critical mineral, Net import reliance
Lists, data & organisations An EU critical raw material that is also needed for green, digital, defence or space technology.
The 17 strategic raw materials are a subset of the EU critical list. The Critical Raw Materials Act sets targets for them and can speed up permits for projects that produce them.
Where you’ll see this: 29 material pages
Related: Critical Raw Materials Act, Critical raw material (EU)
Also called: substitution
A different material that can do the same job if the usual one becomes scarce.
A good substitute softens a supply shock: buyers can switch. For many critical minerals the substitutes are worse, more expensive or need products to be redesigned, which is part of what makes the material critical.
Substitution also works across technologies, as when battery makers use cathode chemistries that need less cobalt.
Example: Lithium iron phosphate (LFP) batteries avoid cobalt and nickel entirely.
Where you’ll see this: 76 material pages
Related: Recycling, End use, LFP
Metals, alloys & compounds A compound containing sulfur and oxygen; nickel and cobalt sulfate are key battery chemicals.
Battery cathode makers buy nickel, cobalt and manganese as sulfates, dissolve them, and turn them into cathode material.
Where you’ll see this: 11 material pages
Related: NMC / NCM, Mixed hydroxide precipitate, Hydroxide
Metals, alloys & compounds A nickel- or cobalt-based alloy that stays strong at extreme temperatures, used in jet engines.
Superalloys are used in jet-engine turbines, gas turbines for power plants and rocket engines. They rely on small amounts of critical minerals such as cobalt, rhenium, tantalum, niobium and hafnium, which are hard to replace.
Example: About half of US cobalt use goes into superalloys, mainly for aircraft engines.
Where you’ll see this: 15 material pages
Related: Alloy, Refractory
A material that carries electricity with no resistance at all when cooled far enough.
Niobium–titanium and niobium–tin wires are used to make the powerful magnets in MRI scanners and particle accelerators.
Where you’ll see this: 4 material pages
Related: Alloy
How much of the world's supply comes from a single country or company.
When one country produces most of a material, any decision or disruption there affects buyers everywhere. Supply concentration is one of the five drivers in the risk tracker.
The tracker uses the largest single country's share at the most concentrated stage, mining or refining, whichever is higher.
See every material's rating →
Related: Supply-risk rating, Refining, Mine production, Export control
Lists, data & organisations This site's five-level rating, from Low to Critical, of how hard a material may be to get over the next year.
The rating looks at the near term, roughly 12 months: can a buyer outside China and outside the producing country get the material in the usual form, volume and lead time?
It combines five drivers: supply concentration, export controls, policy and tariffs, operational disruption, and demand shocks. Every change has a dated explanation with sources. It is not a price forecast or investment advice.
Open the risk tracker →
Related: Supply concentration, Export control, Tariff