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The uranium journey · data

One tonne of ore, from the mine to the repository

Scroll, or step through with the stage buttons (arrow keys, Home and End work while a button has focus). Every figure in the scenes and the balance comes from the verified fact base, and the balance recomputes when you change the ore grade; the who-does-it panels count records of the named datasets. Pounds of U₃O₈ are the unit the market quotes; kilograms are of the substance named.

From about 0.02% U, the leanest ore some mines work, to 20% U, the average grade of the richest Canadian deposits (sc_ore_grade_typical). Default 0.10% U, the typical minimum of current mines; the slider is logarithmic.

Mining: on the left, in-situ recovery wells push leach solution through a sandstone ore layer and pump it back to the plant; on the right, an open pit is cut bench by bench into an ore body and the ore piled at the surface.over 55% ISR (2024)about 40% conventional (2024)
01 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Stage 1 · Ore, 0.02 to 20% U

Mine

1,000 kg ore · its uranium as U₃O₈: 2.600 lb1 t of ore at 0.1% U (sc_ore_grade_typical: most deposits supporting current mines grade above 0.10% U); uranium content = ore mass × grade

Mill to yellowcake: crushed ore is leached in acid, the dissolved uranium is precipitated, filtered and dried to U₃O₈ concentrate and packed into steel drums.U₃O₈: 84.8% U by mass1.18 kg U₃O₈ / t oreabout 400 kg U₃O₈ a drum
02 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Stage 2 · U₃O₈ concentrate

Mill → yellowcake

1.179 kg U₃O₈ · its uranium as U₃O₈: 2.600 lbkg U × 1.17924 (pu_unit_tu_to_tu3o8: 1 tU is contained in 1.17924 t U₃O₈); milling recovery losses not deducted because no verified figure exists, so this is an upper bound

Conversion: uranium oxide concentrate is dissolved, purified, turned into uranium tetrafluoride with hydrogen fluoride and into uranium hexafluoride with fluorine, then condensed into a 48Y cylinder.U₃O₈HFF₂UF₆ gas48Y cylinderholds 12.5 t UF₆drumsdissolvepurifyUO₂ → UF₄fluorinate1.47 kg UF₆ from one tonne of ore0.5% conversion loss booked
03 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Stage 3 · U₃O₈ → UF₆

Conversion

1.471 kg UF₆ · its uranium as U₃O₈: 2.587 lbkg U after the conversion loss (0.995 kg U) × 1.47889. Fact in full: "1 lb of uranium as UF6 corresponds to 1.47889 lb of UF6; converting U3O8 to UF6 is usually booked with a 0.5% conversion loss (1 lb U3O8 = 0.84376 lb U in UF6)."

Enrichment: natural uranium hexafluoride passes a cascade of centrifuge stages and splits into a small product stream richer in uranium-235 and a large tails stream.feed 0.995 kg U0.711% U-235product 0.097 kg U, 5.0% U-235tails 0.898 kg U, 0.25% U-235about 0.76 SWUfeed = product + tails
04 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Natural uranium fed to enrichment0.995U2.587
Enriched product (5% U-235)0.097Un/a
Stage 4 · LEU 3 to 5%, HALEU to 20%

Enrichment

0.097 kg Ufeed 0.995 kg U ÷ 10.30; the divisor is arithmetic from the assays, (5 − 0.25) ÷ (0.711 − 0.25), with natural uranium at 0.711 wt % U-235, derived from the NIST atom fractions in fi_natural_abundance_precise (0.7204 atom % × 235.04 ÷ (0.7204 × 235.04 + 99.2796 × 238.03); the WNA SWU figure assumes the same 0.711 %); 0.8 SWU at 7.9 SWU per kg product (sc_swu_per_kg_product); not restated as lb U₃O₈: enriched and depleted uranium are not quoted that way (the feed row carries the U₃O₈ equivalent)

Fuel fabrication: UF₆ becomes UO₂ powder, pressed into ceramic pellets, stacked in rods and bundled into a square assembly.UF₆UO₂ powderpellet, about 1 cmrod17 × 17 assembly193 assemblies and over 50,000 rods in one large core
05 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Natural uranium fed to enrichment0.995U2.587
Enriched product (5% U-235)0.097Un/a
Depleted tails (0.25% U-235)0.898Un/a
UO₂ pressed into pellets0.110UO₂n/a
Stage 5 · Pellets, rods, assemblies

Fuel fabrication

0.110 kg UO₂enriched uranium 0.097 kg U × 1.1344 (molar masses of UO₂ and U, stoichiometry rather than a sourced figure); not restated as lb U₃O₈: enriched and depleted uranium are not quoted that way (the feed row carries the U₃O₈ equivalent)

Reactor: fuel assemblies in the core of a pressure vessel, control rods withdrawing as the cycle runs, coolant carrying heat to a steam generator.steam generatorcore and control rodscycle 12 to 18 monthsburnup about 50 GWd/t(typical in the USA)over 90% of the energyis still in the fuel
06 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Natural uranium fed to enrichment0.995U2.587
Enriched product (5% U-235)0.097Un/a
Depleted tails (0.25% U-235)0.898Un/a
UO₂ pressed into pellets0.110UO₂n/a
Spent fuel after irradiation0.110spent fueln/a
Stage 6 · Refuelled every 12 to 18 months

Reactor

0.110 kg spent fueltotal mass taken as unchanged from the UO₂ loaded; uranium remaining = 95.6% of the 0.097 kg U loaded, reading wa_spent_fuel_composition (about 95.6% uranium, 2.9% stable fission products, 0.9% plutonium, …) as shares of the heavy metal and fission products, which sum to 100% without the oxygen; not restated as lb U₃O₈ because it is no longer natural uranium

Spent fuel pool: used assemblies cool under water for years while their heat and radioactivity fall steeply, then more slowly.at least 5 years under waterheat and activity fallingtime in the pool →used fuel: 95.6% U, 0.9% Pu3.4% fission products
07 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Natural uranium fed to enrichment0.995U2.587
Enriched product (5% U-235)0.097Un/a
Depleted tails (0.25% U-235)0.898Un/a
UO₂ pressed into pellets0.110UO₂n/a
Spent fuel after irradiation0.110spent fueln/a
Stage 7 · At least 5 years of cooling

Spent fuel pool

0.110 kg spent fueltotal mass taken as unchanged from the UO₂ loaded; uranium remaining = 95.6% of the 0.097 kg U loaded, reading wa_spent_fuel_composition (about 95.6% uranium, 2.9% stable fission products, 0.9% plutonium, …) as shares of the heavy metal and fission products, which sum to 100% without the oxygen; not restated as lb U₃O₈ because it is no longer natural uranium

Dry cask: cooled assemblies are moved from the pool into a steel canister, sealed and set in a concrete overpack; a transport cask waits on a rail car.poolabout 40 assembliesup to 45 kWtransport caskabout 125 t loadedover 25,000 shipmentswithout a release
08 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Natural uranium fed to enrichment0.995U2.587
Enriched product (5% U-235)0.097Un/a
Depleted tails (0.25% U-235)0.898Un/a
UO₂ pressed into pellets0.110UO₂n/a
Spent fuel after irradiation0.110spent fueln/a
Stage 8 · Decades of storage

Dry cask

0.110 kg spent fueltotal mass taken as unchanged from the UO₂ loaded; uranium remaining = 95.6% of the 0.097 kg U loaded, reading wa_spent_fuel_composition (about 95.6% uranium, 2.9% stable fission products, 0.9% plutonium, …) as shares of the heavy metal and fission products, which sum to 100% without the oxygen; not restated as lb U₃O₈ because it is no longer natural uranium

Repository: a canister descends a shaft to a gallery deep in the host rock and is sealed in a disposal cell; a ladder shows how long caesium-137 and plutonium-239 take to halve.0 m500 mhost rockCigeo, France: about 500 m down0.11 kg spent fuel from one tonne of ore1 year1,000 years1 million yearsCs-137 halves in 30.08 yearsPu-239 in 24,110 years
09 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Natural uranium fed to enrichment0.995U2.587
Enriched product (5% U-235)0.097Un/a
Depleted tails (0.25% U-235)0.898Un/a
UO₂ pressed into pellets0.110UO₂n/a
Spent fuel after irradiation0.110spent fueln/a
Stage 9 · Deep geological disposal

Repository

0.110 kg spent fueltotal mass taken as unchanged from the UO₂ loaded; uranium remaining = 95.6% of the 0.097 kg U loaded, reading wa_spent_fuel_composition (about 95.6% uranium, 2.9% stable fission products, 0.9% plutonium, …) as shares of the heavy metal and fission products, which sum to 100% without the oxygen; not restated as lb U₃O₈ because it is no longer natural uranium

Reprocessing: used fuel is sheared and dissolved, separated into uranium, plutonium and fission products; the fission products are vitrified and the uranium and plutonium return to fuel fabrication.dissolveseparateuranium 95.6%plutonium 0.9%fission products 3.4%in glassMOX fuel back to fabricationLa Hague: 1,700 t a yearabout 30% of all used fuel so far has been reprocessed
10 / 10
So farkgoflb U₃O₈
Ore mined1,000ore2.600
Uranium contained in the ore1.000U2.600
Yellowcake leaving the mill1.179U₃O₈2.600
Natural UF₆ leaving conversion1.471UF₆2.587
Natural uranium fed to enrichment0.995U2.587
Enriched product (5% U-235)0.097Un/a
Depleted tails (0.25% U-235)0.898Un/a
UO₂ pressed into pellets0.110UO₂n/a
Spent fuel after irradiation0.110spent fueln/a
Stage 10 · La Hague, Rokkasho, MOX

Reprocessing

0.110 kg spent fueltotal mass taken as unchanged from the UO₂ loaded; uranium remaining = 95.6% of the 0.097 kg U loaded, reading wa_spent_fuel_composition (about 95.6% uranium, 2.9% stable fission products, 0.9% plutonium, …) as shares of the heavy metal and fission products, which sum to 100% without the oxygen; not restated as lb U₃O₈ because it is no longer natural uranium

Sources: the explainer fact base, verified 9 Oct 2026; each fact links to the page read. The balance is arithmetic on those facts (see the table below); milling recovery is not deducted, so the yellowcake line is an upper bound. The who-does-it panels count records of the reactors, mines and fuel-cycle facilities datasets, each named with its sources and access date.

Mass balance · data

The balance behind the journey, line by line

The running balance the journey above animates, at the default grade of one tonne of ore. Each row names the substance it weighs, because a kilogram of UF₆ is not a kilogram of uranium: the lb column converts that same substance at 2.20462 lb per kg, and the last column restates the uranium it contains in pounds of U₃O₈, the unit the market quotes. Every line rests on a verified fact or on arithmetic between two facts, as stated in the basis column. Milling recovery is not deducted because no verified figure exists yet; the result is therefore an upper bound.

Mass balance for one tonne of ore
StageSubstance weighedkglb (same substance)Uranium in it, kg Uas lb U₃O₈BasisFacts
Ore minedore1,0002,2051.0002.6001 t of ore at 0.1% U (sc_ore_grade_typical: most deposits supporting current mines grade above 0.10% U); uranium content = ore mass × gradesc_ore_grade_typical, pu_unit_lb_kg, pu_unit_kgu_to_lb_u3o8
Uranium contained in the oreU1.0002.2051.0002.600uranium metal; pounds of U₃O₈ equivalent = kg U × 2.59979 (pu_unit_kgu_to_lb_u3o8)sc_ore_grade_typical, pu_unit_kgu_to_lb_u3o8
Yellowcake leaving the millU₃O₈1.1792.6001.0002.600kg U × 1.17924 (pu_unit_tu_to_tu3o8: 1 tU is contained in 1.17924 t U₃O₈); milling recovery losses not deducted because no verified figure exists, so this is an upper boundpu_unit_tu_to_tu3o8, pu_u3o8_uranium_content, pu_unit_lb_kg
Natural UF₆ leaving conversionUF₆1.4713.2440.9952.587kg U after the conversion loss (0.995 kg U) × 1.47889. Fact in full: "1 lb of uranium as UF6 corresponds to 1.47889 lb of UF6; converting U3O8 to UF6 is usually booked with a 0.5% conversion loss (1 lb U3O8 = 0.84376 lb U in UF6)."pu_unit_uf6, pu_unit_lb_kg
Natural uranium fed to enrichmentU0.9952.1940.9952.587the uranium inside the UF₆ above: 1.000 kg U × (1 − 0.5%) per the conversion-loss convention in pu_unit_uf6; assay 0.711 wt % U-235 (from fi_natural_abundance_precise, see the product row; industry pages round it to 0.7 %)pu_unit_uf6, fi_natural_abundance_precise
Enriched product (5% U-235)U0.0970.2130.097n/afeed 0.995 kg U ÷ 10.30; the divisor is arithmetic from the assays, (5 − 0.25) ÷ (0.711 − 0.25), with natural uranium at 0.711 wt % U-235, derived from the NIST atom fractions in fi_natural_abundance_precise (0.7204 atom % × 235.04 ÷ (0.7204 × 235.04 + 99.2796 × 238.03); the WNA SWU figure assumes the same 0.711 %); 0.8 SWU at 7.9 SWU per kg product (sc_swu_per_kg_product); not restated as lb U₃O₈: enriched and depleted uranium are not quoted that way (the feed row carries the U₃O₈ equivalent)fi_natural_abundance_precise, sc_swu_per_kg_product
Depleted tails (0.25% U-235)U0.8981.9810.898n/afeed 0.995 kg U minus product 0.097 kg U; the balance closes by construction; not restated as lb U₃O₈: enriched and depleted uranium are not quoted that way (the feed row carries the U₃O₈ equivalent)sc_swu_per_kg_product
UO₂ pressed into pelletsUO₂0.1100.2420.097n/aenriched uranium 0.097 kg U × 1.1344 (molar masses of UO₂ and U, stoichiometry rather than a sourced figure); not restated as lb U₃O₈: enriched and depleted uranium are not quoted that way (the feed row carries the U₃O₈ equivalent)sc_fuel_pellet_size
Spent fuel after irradiationspent fuel0.1100.2420.092n/atotal mass taken as unchanged from the UO₂ loaded; uranium remaining = 95.6% of the 0.097 kg U loaded, reading wa_spent_fuel_composition (about 95.6% uranium, 2.9% stable fission products, 0.9% plutonium, …) as shares of the heavy metal and fission products, which sum to 100% without the oxygen; not restated as lb U₃O₈ because it is no longer natural uraniumwa_spent_fuel_composition, mu_spent_fuel_energy
Sources: the explainer fact base, verified 9 Oct 2026 (each fact id links to the page read). Pounds are kilograms × 2.20462 of the substance named on the row (pu_unit_lb_kg); "as lb U₃O₈" is the uranium content × 2.59979 (pu_unit_kgu_to_lb_u3o8), the unit the market quotes. Arithmetic steps are labelled; they are not sourced figures.
Pricing and units · data

What the price quotes

The periodic table talks about uranium-235 and uranium-238. The market quotes pounds of U₃O₈, the oxide in the concentrate that leaves the mill. Resources, production and reactor requirements are usually stated in tonnes of uranium metal (tU). The factors below convert between them.

1 tU= 1.17924 t U₃O₈
1 kgU= 2.59979 lb U₃O₈
$89.63spot, per lb U₃O₈, Sep 2026
Factors: TradeTech - Unit Conversion Table, 9 Oct 2026 (pu_unit_tu_to_tu3o8, pu_unit_kgu_to_lb_u3o8). Spot: Cameco - Uranium Price (industry average of the month-end prices published by UxC and TradeTech), month-end 9 Oct 2026.

Uranium spot and long-term price indicators, monthly, USD per lb U₃O₈, 1988 to 2026

Source: Cameco - Uranium Price (industry average of the month-end prices published by UxC and TradeTech) (industry average of the month-end UxC and TradeTech prices), as of 9 Oct 2026. Latest: Sep 2026, spot $89.63, long-term $96.50 per lb U₃O₈. UxC and TradeTech weekly data are paywalled.

Units and conversions

1 tonne of uranium (tU) is contained in 1.17924 tonnes of U3O8.

TradeTech - Unit Conversion Table, 9 Oct 2026· primary source

1 kg of uranium is contained in 2.59979 lb of U3O8.

TradeTech - Unit Conversion Table, 9 Oct 2026· primary source

U3O8 contains about 85% uranium by mass (1 / 1.17924 = 84.8%).

WNA - Uranium Mining Overview, 6 Oct 2026· reputable secondary

1 lb = 0.45359 kg and 1 kg = 2.20462 lb; a metric tonne is 2,204.62 lb and a short ton 2,000 lb.

TradeTech - Unit Conversion Table, 9 Oct 2026· primary source

1 lb of uranium as UF6 corresponds to 1.47889 lb of UF6; converting U3O8 to UF6 is usually booked with a 0.5% conversion loss (1 lb U3O8 = 0.84376 lb U in UF6).

TradeTech - Unit Conversion Table, 9 Oct 2026 · TradeTech convention, 0.5% conversion loss· primary source

How utilities contract

Prices in term contracts are often related to the spot price indicator at the time of delivery, and producers selling directly to utilities obtain a higher price than the spot market, reflecting security of supply.

WNA - Uranium Markets, 23 Aug 2024· reputable secondary

The spot market's share of uranium trade roughly doubled from 2008 to about one-quarter of volume over the last decade; most trade is via 3-15 year term contracts.

WNA - Uranium Markets, 23 Aug 2024 · last decade per WNA (page updated 23 Aug 2024)· reputable secondary

Most uranium trade is via term contracts of 3-15 years' duration.

WNA - Uranium Markets, 23 Aug 2024· reputable secondary

87% of the uranium delivered to US utilities in 2025 came under long-term contracts at a weighted-average US$55.91 per lb, and 13% under spot contracts at US$76.01 per lb.

US EIA - 2025 Uranium Marketing Annual Report, 13 Aug 2026 · 2025 deliveries· primary source

By origin, US utilities' 2025 uranium came 32% from Canada, 28% from Kazakhstan, 15% from Australia, 7% from Uzbekistan, 4% from Namibia and 7% from the United States.

US EIA - 2025 Uranium Marketing Annual Report, 13 Aug 2026 · 2025 deliveries· primary source

US utilities signed 22 new uranium purchase contracts in 2025.

US EIA - 2025 Uranium Marketing Annual Report, 13 Aug 2026 · 2025· primary source

Maximum deliveries under US utilities' existing purchase contracts for 2026-2035 total 174 million lb U3O8e.

US EIA - 2025 Uranium Marketing Annual Report, 13 Aug 2026 · 2026-2035 cumulative· primary source

US utilities' unfilled uranium requirements for 2025-2035 were 186 million lb U3O8e, i.e. demand not yet covered by contracts.

US EIA - 2025 Uranium Marketing Annual Report, 13 Aug 2026 · 2025-2035 cumulative, as of end-2025· primary source

US commercial uranium inventories (owners/operators and suppliers) totalled 170 million lb U3O8e at the end of 2025.

US EIA - 2025 Uranium Marketing Annual Report, 13 Aug 2026 · end-2025· primary source