The rule
No figure appears on this site without the period it refers to and the dataset it came from. Where a source publishes a code instead of a number, that code is printed and explained — never converted into a blank, a zero or a dash that implies zero.
Production and reserves
These come from the USGS Mineral Commodity Summaries 2026 data release, loaded row by row and stored verbatim. Figures for 2025 are USGS estimates; 2024 and earlier are as reported. Units differ by commodity and are shown on every table, because they are not interchangeable: some are contained metal, some are gross weight of ore or concentrate, some are oxide equivalent. Lithium is reported as contained metal, not carbonate. Rare earths are reported as oxide equivalent. Iron ore has separate usable-ore and iron-content lines that must never be compared.
The source's reporting codes are preserved and rendered in words: W means withheld to avoid disclosing an individual company's proprietary data; XX means not available; NA means not applicable; a dash means the source reported zero. A withheld value is not a small value.
Country rows will not always add to the world total. The source rounds each figure independently, and often carries an unbroken "other countries" line. We do not force the arithmetic to close.
Shares and percentages
Where a share of world production or reserves is shown, it is computed as the country's own published figure divided by the same table's published world total, for the same year and the same unit. If either side is withheld, no share is shown.
Prices
Price series shown on material pages are annual averages as published by the USGS, on the exact basis named beneath each chart — for example "battery-grade lithium carbonate" rather than "lithium". They are reference annual averages, not live market quotes, and a single annual number hides very large intra-year movement.
Material intensity
Intensity figures — how much of a material one EV, one megawatt or one magnet contains — are given as ranges, with the basis stated (contained metal, oxide, gross weight) and the unit they are quoted per. They are compiled from published technology studies and from chemistry that can be checked: a lithium-ion cell needs roughly 0.09–0.11 kg of contained lithium per kilowatt-hour, so a 75 kWh pack is around 7 kg, and the page says so. Real designs vary by manufacturer, chemistry and model year, and intensities generally fall over time. These numbers are for reasoning about scale. They are not a bill of materials and must not be used as one.
Mines, plants and companies
Operators, owners, mining methods and deposit types are compiled from public company reporting and standard reference works. Where a stake has changed recently we describe the relationship rather than assert a percentage that may already be stale. Scale is described qualitatively — "one of the largest copper mines by output" — unless the operator publishes a figure we can attribute.
Company share prices come from Financial Modeling Prep and are delayed, typically 15–20 minutes or more. Where no price is shown, the company page states the specific reason: the company is state-owned, or unlisted, or listed on an exchange this site's quote provider does not carry. "No price" never means "not traded".
Photographs
Every photograph is a real image from Wikimedia Commons under a public-domain, CC0, CC BY or CC BY-SA licence. Non-commercial and no-derivatives licences are excluded automatically rather than by judgement. Each image stores its title, author, licence, licence URL and file page, and all of that is printed beneath it. No image is used on more than one page, so a picture on this site is always specific to the thing it illustrates.
AI assistance
Long-form explanatory text and the four-level material descriptions are drafted with AI assistance and edited. The model is given the site's own data and is not permitted to introduce figures; every number that appears in prose also appears in a sourced table. The "Ask the Data" tool answers only from a JSON extract of this site's database and is instructed to say when the answer is not there. In-house data briefs on the news page are labelled as such and are never attributed to a publisher.
Where this can still be wrong
Editions change: reserve estimates are revised, and a 2025 estimate becomes a 2025 actual. Ownership changes faster than any reference work. Intensity ranges are wide for a reason and the low end of one may be below the high end of another technology. And a public dataset is a snapshot of what its compilers could verify, not of physical reality. Check the primary source before anything depends on it.