We compare the sum of BGS World Mineral Statistics national returns against the USGS world-production estimate for the same material, over the years both cover. These are independent compilations, but not independent measurements — both rest largely on the same national statistical returns, so they can agree and still both be wrong. Agreement therefore tells you we have paired the right forms and read the units correctly. It is not evidence that a number is true, and a disagreement does not make either body wrong. Most disagreement here is definitional.
The disagreements are the content
One was unexplained until recently, and it turned out not to be an error in anyone’s data. A second, cobalt, was “explained” here and has been withdrawn: the gap was our own double count, not the data (see below).
BGS cement has ~32 reporting countries, led by Turkey, Germany, Italy and Spain. China alone produces roughly 2.4 of the world’s ~4.2 billion tonnes, and it does not appear at all. The panel is a Europe-weighted subset, not a world census — so its sum must never be used as a world denominator. Nothing here is a data error; the series simply does not mean what a reader would assume it means.
All 53 materials
Ordered by how far apart the two counts are — least comparable first, because those rows carry the information. Ratio = median (BGS national sum ÷ USGS world estimate) over the overlapping years.
| Material | BGS form paired | Ratio | Reporters | Status | What the difference is |
|---|---|---|---|---|---|
| tantalum † | tantalum and niobium minerals | 122.80 | 6 | not comparable | BGS publishes tantalum AND niobium minerals as one gross-ore series; USGS publishes contained tantalum alone. Different numerator and different basis. |
| beryllium † | beryl | 24.98 | 6 | not comparable | BGS counts BERYL (the ore mineral); USGS counts contained beryllium. Beryl is roughly 4% Be. |
| chromium | chromium ores and concentrates | 2.82 | 19 | not comparable | BGS counts chromite ORE at gross weight; USGS counts contained chromium. |
| manganese | manganese ore | 2.74 | 27 | not comparable | BGS counts manganese ORE at gross weight; USGS counts CONTAINED manganese. Ore grades ~30-50% Mn, which is the whole ratio. |
| cement | cement, finished | 0.07 | 32 | not comparable | RESOLVED - not a unit slip: both series are in tonnes. It is a coverage hole. BGS cement has ~33 reporters led by Turkey, Germany, Poland, Italy and Spain; CHINA AND INDIA ARE ABSENT, and China alone is ~2.4 of the ~4.2 billion tonne world total. The BGS cement panel is a Europe-weighted sub-panel, not a world census, so its sum must never be used as a world denominator. |
| bromine | bromine | 1.60 | 9 | not comparable | Unresolved: likely a compound-vs-element basis difference. |
| titanium | titanium minerals | 1.46 | 19 | not comparable | BGS counts titanium MINERALS (ilmenite + rutile, gross); USGS reports on a TiO2-content basis. |
| bismuth | bismuth, mine | 0.56 | 8 | not comparable | Unresolved. Both sides are now MINE output (the USGS world mine series entered the cube on 16 Sep 2026; it ends in 2013, so only 2005-2013 overlap), and BGS national returns sum to about half of it. The earlier note blamed a stage mismatch - true only while the USGS side was refinery production. |
| boron | borates | 1.28 | 10 | not comparable | BGS counts borate MINERALS (gross); USGS reports boron content. |
| graphite | graphite | 1.27 | 16 | not comparable | Unresolved: natural-graphite scope differs between the two. |
| mica | mica | 0.79 | 20 | not comparable | Unresolved: sheet vs scrap/flake mica scope differs. |
| gallium † | gallium, primary | 0.81 | 5 | within 25% | BGS gallium coverage is thin and USGS publishes an estimate rather than a census; neither side is a measured world total. |
| wollastonite † | wollastonite | 1.19 | 7 | within 25% | Within compilation tolerance; few producers, so one country revision moves the ratio noticeably. |
| selenium | selenium, refined | 1.17 | 16 | within 25% | Within compilation tolerance; refinery-output coverage differs by year. |
| germanium † | germanium metal | 0.83 | 3 | within 25% | BGS carries only 3-4 reporting countries for germanium metal, so its sum is not a world total; USGS states outright that reliable world estimates cannot be made. The near-agreement here is coincidence, not corroboration - this is the material that prompted the whole check. |
| feldspar | feldspar | 1.15 | 52 | within 25% | Within compilation tolerance. No structural basis difference identified; the two bodies revise on different schedules and BGS country coverage varies by year. |
| iron ore | iron ore | 0.87 | 46 | within 25% | Iron ore scope differs: crude-ore vs usable-ore reporting is not consistent between the two bodies. |
| talc | talc | 0.87 | 36 | within 25% | Within compilation tolerance; talc/pyrophyllite scope differs slightly. |
| magnesium | magnesite | 1.10 | 23 | within 10% | — |
| diatomite | diatomite | 0.92 | 27 | within 10% | — |
| indium | indium, refinery | 0.93 | 11 | within 10% | — |
| rare earths † | rare earth oxides | 1.07 | 6 | within 10% | — |
| iodine | iodine | 1.07 | 9 | within 10% | — |
| perlite | perlite | 1.06 | 19 | within 10% | — |
| tellurium † | tellurium, refined | 0.94 | 6 | within 10% | — |
| zirconium | zirconium minerals | 0.95 | 16 | within 10% | — |
| cobalt | cobalt, mine | 1.05 | 19 | within 10% | — |
| salt | salt | 0.95 | 101 | within 10% | — |
| baryte | barytes | 1.04 | 35 | within 10% | — |
| lithium † | lithium minerals | 0.96 | 7 | within 10% | — |
| arsenic † | arsenic, white | 1.03 | 7 | within 10% | — |
| gypsum | gypsum and plaster | 1.03 | 84 | within 10% | — |
| tin | tin, mine | 1.03 | 24 | within 10% | — |
| asbestos † | asbestos | 0.97 | 5 | within 10% | — |
| rhenium † | rhenium | 0.97 | 7 | within 10% | — |
| vanadium † | vanadium, mine | 1.02 | 4 | within 10% | — |
| tungsten | tungsten, mine | 1.02 | 20 | within 10% | — |
| strontium † | strontium minerals | 1.02 | 6 | within 10% | — |
| nickel | nickel, mine | 0.98 | 27 | within 10% | — |
| gold | gold, mine | 1.01 | 98 | within 10% | — |
| fluorspar | fluorspar | 0.99 | 24 | within 10% | — |
| mercury | mercury | 1.01 | 9 | within 10% | — |
| antimony | antimony, mine | 1.01 | 17 | within 10% | — |
| bauxite | bauxite | 0.99 | 31 | within 10% | — |
| platinum | platinum group metals, mine | 0.99 | 11 | within 10% | — |
| phosphate | phosphate rock | 1.01 | 36 | within 10% | — |
| lead | lead, mine | 1.01 | 46 | within 10% | — |
| potash | potash | 1.01 | 12 | within 10% | — |
| silver | silver, mine | 1.01 | 68 | within 10% | — |
| zinc | zinc, mine | 1.01 | 51 | within 10% | — |
| molybdenum | molybdenum, mine | 1.00 | 15 | within 10% | — |
| cadmium | cadmium | 1.00 | 18 | within 10% | — |
| copper | copper, mine | 1.00 | 54 | within 10% | — |
- cobalt (2026-09-16): Not comparable (ratio 0.60), "resolved" as DR Congo artisanal output missing from BGS, with USGS world output said to climb to 294 kt in 2020. The USGS side summed two world series: mine production and refinery production, each 147 kt in 2020. Compared with mine production alone, the BGS sum agrees within 10% (ratio 1.05). The DR Congo explanation was built on the doubled figure and is withdrawn.
What this page does not claim
- Not verification. Two compilations sharing the same national returns cannot verify each other.
- Not accuracy, and not ground truth. Neither body measures the ore; both collect what is reported.
- Agreement within 10% does not make a figure correct, and the band is wide.
- A material that does not pair is not thereby worse — usually the two are simply counting different objects, such as gross ore against contained metal.
- Where the two differ, this page does not declare the atlas’s number the winner.
How far the other agency sits from these figures. The numbers on this page are BGS. For the commodities where the atlas has measured it, the USGS world total for the same commodity and stage differs from the BGS one by a median of: graphite 30.7%, antimony 13.1%, cobalt 12.7%, tungsten 6.9%, rare earths 5.7%, copper 0.6% (median absolute difference over 2002–2024, unsigned). That is a disagreement between two compilations, not an error bar and not a correction of either — it can be measurement, definition, coverage or vintage. The same measurement also shows how far the USGS moves its own current-year estimate, which is the figure to check before treating a how firm is a current-year production figure?
figure?build_pairing.py, never inferred by matching material names: a ratio between “manganese ore, gross weight” and “manganese, contained metal” is a category error, not a disagreement. Both series are read from the atlas’s harmonised cube, which keeps every source’s native codes and units alongside the common labels. Data: BGS World Mineral Statistics and USGS Historical Statistics → pairing.json.