Lesson 3 of 8
Reading a miner
Newmont reported 118.2 million ounces of gold reserves at 31 December 2025, estimated at an assumed price of 2,000 dollars. The asset depends on the price.
By Javier Sanz
Founder of ValueScreener. Built Ninety Nine, a securities services provider, and sold it to a tier-one global bank; ran operations and internationalization at Alpaca, the brokerage API.
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In one minute
- A mining reserve is not a physical fact alone: it is the quantity economic to extract at an assumed price, so the asset quantity moves when the price assumption moves.
- Newmont reported attributable proven and probable gold reserves of 118.2 million ounces at 31 December 2025, estimated at a gold price assumption of 2,000 dollars an ounce against 1,700 for 2024.
- All-in sustaining cost per ounce sold ranged from 696 dollars to 1,921 dollars across sites inside the same company in 2025, which is the cost curve made visible.
Everything unusual about a mining company's accounts follows from one fact. The principal asset is in the ground, its quantity is an estimate, and the estimate depends on a price that somebody chose.
Newmont gold reserves at 31 December 2025
| Category | Tonnage, thousands of tonnes | Grade, grams a tonne | Ounces, thousands |
|---|---|---|---|
| Proven reserves | 490,900 | 1.04 | 16,500 |
| Probable reserves | 3,416,100 | 0.93 | 101,800 |
| Proven and probable | 3,907,000 | 0.94 | 118,200 |
Metallurgical recovery across the total is 81 percent.
The price inside the asset
The filing states it plainly: reserves for 2025 and 2024 were estimated at gold price assumptions of 2,000 and 1,700 dollars an ounce respectively, and it attributes the increase in the assumption to its assessment of historical pricing trends, consensus price forecasts and the effects of inflation.
Raise the assumed price and material previously uneconomic becomes a reserve. Lower it and reserves disappear without a shovel moving. So a year-on-year change in reserve ounces is at least two things at once: what was mined and found, and what price was assumed.
That is why the price assumption is the first thing to read in a mining filing, before the reserve number it produced.
Grade is the second number
A grade of 0.94 grams a tonne means about one gram of gold in every tonne of rock moved. Grade sets how much material has to be handled for each ounce, so it sets the cost more directly than any operating decision does.
Two mines with identical reserve ounces and different grades are different businesses. The higher-grade one moves less rock, burns less fuel and employs fewer trucks for the same output, and no amount of management skill closes that gap.
The cost curve inside one company
All-in sustaining cost per ounce sold, which the company reports as a non-GAAP measure and reconciles, ranged widely across sites in 2025: 696 dollars at Ahafo North, 1,253 at Cadia, 1,494 at Ahafo South, 1,514 at Boddington, 1,607 at Lihir, 1,716 at Tanami and 1,921 at Merian.
That spread is the whole subject. A price fall that leaves the lowest-cost site profitable can make the highest-cost one uneconomic, and it is the site-level disclosure rather than the company average that says which.
The rest of the year in context
The company produced approximately 6 million attributable ounces of gold in 2025, a decrease of 14 percent on the prior year, which it attributes largely to the effect of divestments. It reported net income from continuing operations attributable to stockholders of 7,085 million dollars, operating cash flow from continuing operations of 10,334 million, and ended the year with 7.6 billion dollars of consolidated cash.
Those figures are the output. The reserve table, the grade and the cost curve are the inputs that determine whether they repeat.
Check yourself
Why is a mining reserve not purely a physical quantity?
- Because it is measured by a third party
- Because it is the quantity economic to extract at an assumed price, so the assumption changes the quantity
- Because grades are estimates
Show the answer
Answer: B.
Newmont's 2025 reserves were estimated at an assumed 2,000 dollars an ounce against 1,700 for 2024, which the filing attributes to pricing trends, consensus forecasts and inflation.What does a grade of 0.94 grams a tonne tell you?
- That the gold is of low purity
- That about one gram of gold is recovered from each tonne of rock moved, which sets the cost of production more directly than any operating decision
- That the reserve is uneconomic
Show the answer
Answer: B.
Grade sets how much material has to be handled per ounce. Two mines with the same ounces and different grades are different businesses.What does the spread from 696 to 1,921 dollars an ounce across sites show?
- That the measure is unreliable
- That a price fall can leave one site profitable and another uneconomic inside the same company, so site-level disclosure matters more than the average
- That the sites mine different metals
Show the answer
Answer: B.
The company average hides the cost curve. Which sites stay above water at a given price is the question the site table answers.Sources
- Newmont Corporation, Form 10-K for the year ended 31 December 2025, filed 2026-02-19, accession 0001164727-26-000010: the gold reserves table with tonnage, grade, ounces and metallurgical recovery; the gold price assumptions used to estimate reserves for 2025 and 2024; all-in sustaining costs per ounce sold by site; attributable gold production; net income from continuing operations; and operating cash flow from continuing operations.
What this leaves out
- All-in sustaining cost per ounce sold is a non-GAAP measure. The filing presents the figures on a co-product basis, allocating costs to co-product metals by relative sales value, and reconciles them within its non-GAAP section.
- The site figures shown are a selection from a longer table, chosen to show the range rather than to be complete.
- Reserve estimates are prepared under the applicable disclosure rules and depend on the stated price assumption, on grade estimates and on recovery assumptions, each of which the filing discusses.
- Nothing here is a view on Newmont or on any security.