How to value an operating gold mine in Brazil

§ 01 · Method

Which methods are used to value an operating gold mine?

An operating gold mine is valued with three approaches, as recognised by the CIMVal Code (2019) and the VALMIN Code (2015): the income approach, the market approach and the cost approach. For a producing mine with reserves, the income approach carries most of the weight, and the market approach is used to test it.

The codes also require that a valuation be done by a qualified, independent professional and that the inputs be supported by technical work, typically an NI 43-101 or JORC report for reserves and resources. That requirement is the reason a teaser's number is not a valuation: it has no named author, no stated inputs and no technical support.

§ 02 · Income approach

How does a discounted cash flow model value an operating gold mine?

A discounted cash flow (DCF) model values an operating gold mine by projecting, year by year, the gold it will produce and sell, the costs, royalties, taxes and capital it will need, and then discounting the resulting cash flows to today. The sum is the net present value (NPV). Every line of the model should trace to a document.

1. 01

   Tonnes and grade

   Ore to be mined each year and its gold grade, taken from the mine plan and the mineral reserves, not from total resources.

2. 02

   Recovery

   The share of contained gold the plant actually recovers, from metallurgical testwork and, for an operating mine, from its own production history.

3. 03

   Gold price

   A price deck chosen by the buyer, often below spot for conservatism, and tested with sensitivities.

4. 04

   Costs

   Mining, processing and site administration costs, plus sustaining capital, consistent with what the mine has actually spent.

5. 05

   Royalties and taxes

   CFEM at 1.5% of gross gold sales net of sales taxes, the landowner's share, any third-party royalties or streams, and corporate income taxes.

6. 06

   Capital and closure

   Expansion capital if any, working capital, and the closure and rehabilitation cost at the end of mine life.

7. 07

   Discount rate

   A rate that reflects the risk of the asset and the country, chosen by the buyer and disclosed.

Operating mines have one big advantage over projects: history. Past tonnes milled, grades, recoveries and costs are data, not forecasts. A good model starts from the last two or three years of actual performance and explains every difference between that history and the forecast. A forecast that suddenly shows higher grade, better recovery and lower costs than the mine has ever achieved needs a reason, in writing.

The model's results are sensitive to a handful of inputs. Gold price, grade and recovery move revenue directly; costs and discount rate move the margin and the present value. Run sensitivities on each and look at which assumptions the value depends on most. Those are where your due diligence should spend its time.

The discount rate deserves a conversation, not a default. Buyers typically start from a rate they use for producing gold mines and then ask whether this mine and this jurisdiction justify more. A private mine with a short operating history, a licence renewal pending or an unaudited reserve carries more risk than a listed producer, and the rate, or the price structure, should show it. Disclose the rate you used and show the value at rates above and below it, so that every party sees how much of the price depends on that one choice.

§ 03 · Costs

What is AISC, and why does it matter when valuing a gold mine?

All-in sustaining cost (AISC) is a standard measure of what it costs to produce an ounce of gold and keep the mine running, introduced by the World Gold Council in 2013 and since updated. It matters because it is the figure buyers use to compare mines, and because the difference between AISC and the gold price is, roughly, the margin a mine earns before growth capital and taxes.

Private Brazilian mines rarely report AISC. Build it yourself from the accounts and plant records, using the World Gold Council's definitions, so that you can compare the mine with listed peers on equal terms. If the seller supplies an AISC figure, ask for the reconciliation to the financial statements, as the WGC guidance itself recommends.

§ 04 · Market approach

How do comparable deals help value an operating gold mine in Brazil?

Comparable deals anchor the valuation in what buyers have actually paid. Analysts often express them per ounce of reserves or resources, which allows a rough comparison between mines of different sizes. The figure is crude, because it ignores grade, cost and mine life, but it quickly shows whether an asking price is in the right universe.

A simple division illustrates the method, not a valuation: US$1.015 billion over about 3.9 million ounces of reserves is roughly US$260 per reserve ounce, or about US$200 per resource ounce. Those figures reflect three operating mines with a large, documented reserve base, an established operator and the gold price at the time. A small private mine with uncertain reserves and no audited history would not command the same multiple.

Development projects sell for less per ounce because the buyer still carries construction, financing and ramp-up risk. That is why the Tocantinzinho price was partly deferred until production began: the seller shared the risk that the mine might not be built on time.

§ 05 · Brazil

Which Brazil-specific factors change the value of an operating gold mine?

Brazil adds its own lines to the model: the CFEM royalty, the landowner's share, the corporate tax rate and available incentives, the real-dollar exchange rate, licence and dam status, and title risk. Each one can move the value of an operating gold mine materially, and foreign buyers sometimes model them generically.

• Royalties. CFEM on gold is 1.5%. The landowner is entitled to a share of the results by law, and some mines carry private royalties or streams on top.
• Taxes and incentives. The standard combined rate of IRPJ and CSLL is 34%. Projects in the SUDAM (Amazon) and SUDENE (Northeast) regions may qualify for a reduction of income tax on operating profit, subject to approval and time limits. Have a Brazilian tax adviser confirm eligibility.
• Currency. Gold is priced in dollars while most costs are in reais. A weaker real tends to widen the margin; a stronger real compresses it. Model both.
• Licences and dam. A licence close to expiry, conditions not being met or a dam classified as high risk add cost and delay. They belong in the model as capital and time, not only as a footnote.
• Title. A concession in good standing is the base case. Pending obligations, disputes or a PLG behind the story change the risk, and therefore the discount rate or the price structure.

Location matters, too. Power supply, road access in the rainy season, distance to a refinery or export route, and security in some Amazon districts all affect costs and continuity. For an overview of the legal structure a foreign buyer will use, see can foreigners buy a mine in Brazil.

§ 06 · Pitfalls

What do sellers most often overstate in a gold mine valuation?

Sellers most often overstate four things: the ounces that count, the grade, the plant's real capacity and the gold price. Each one inflates the value in a way that a document review can detect.

The vocabulary problem matters here as well. NI 43-101 and JORC are reporting standards. A teaser that describes reserves as “certified” is usually quoting an old or partial report, or none at all. Before any reserve figure goes into a model, ask for the report, its date, its qualified or competent person and the gold price it assumed. Our articles on NI 43-101 and historical estimates and on JORC versus Brazilian ANM reports explain how to read them.

Gold in tailings is a special case. Old tailings can contain recoverable gold, and some Brazilian operations reprocess them profitably. But tailings gold needs its own sampling, metallurgical testing and licensing, and it should be modelled separately from the main ore body, never simply added to the reserve.

§ 07 · Data

What data do you need to value an operating gold mine?

To value an operating gold mine you need technical, operating, financial and legal data, organised so that each assumption in the model points to a source. The checklist below is what we expect to see in a data room before a buyer can price a Brazilian gold mine responsibly.

Gaps in this list do not always kill a deal, but they change its structure. Where the evidence is thin, buyers protect themselves with deferred or contingent payments, as in the Tocantinzinho and CMOC–Equinox terms, with escrow, or with a lower upfront price and a royalty to the seller. A seller who wants the full price upfront should be able to fill the list.

§ 08 · Our method

How BRAZIL MINE supports the valuation of an operating gold mine

We do not sell valuations, and we do not replace an independent valuer or qualified person. What we do is make sure the inputs a valuer needs are real before a buyer spends money on them: the concession, the licence, the dam, the production paper trail and the corporate file. Our founder is a mathematician and land surveyor, and the title and boundary checks are done in-house.

• Verification before presentation: we present a gold mine as operating only when the documents support it.
• KYC and NDA before confidential information is shared.
• Structured data room following the checklist above.
• Buyer's own experts for valuation, technical, legal and tax work.
• No advance fees, and payments only through banks against signed documents.

See current opportunities on our gold mines for sale in Brazil page, and read how to verify a gold mining concession before you model anything.