Mining projects: stages, resource classes and fiscal terms

A mining project takes longer than most other industrial investments to go from an idea to revenue, and most of them never get there. Anyone who invests in, supplies or tenders for a mine needs to know where the project sits on that path, because the risks and the buyers change at each stage.

The stages in order

Exploration comes first. Geologists look for a deposit using mapping, sampling, geophysics and drilling. Almost all of this work ends without a mine. Companies at this stage, often called juniors, raise equity in small amounts and spend it on drilling. Their suppliers are drilling contractors, assay laboratories and geological consultants.

Resource definition follows. Drilling at closer spacing allows a technical team to estimate how much material the deposit holds and at what grade. This estimate is published under a reporting code, and the confidence level matters a great deal, as the next section explains.

Studies come next, and they build in steps. An early-stage study, often called a preliminary economic assessment or scoping study, tests whether the deposit could be worth developing and has wide margins of error. A pre-feasibility study narrows the options. A definitive or bankable feasibility study is detailed enough for lenders and a board to decide. These studies estimate capital cost, operating cost, recovery, price assumptions and returns.

Permitting and community agreements run alongside the studies. In many countries this is the slowest stage, because it depends on environmental approval, water and land rights, and consultation with local and indigenous communities.

Financing and construction come after approval, and the project needs capital for the mine, the plant, power, water, roads and often a port. Construction contracts are among the largest contracts in the sector, and many are won in tenders by engineering and construction firms. Then comes production and ramp-up, with the risk that actual recovery and costs differ from the study. Finally closure and rehabilitation, which in modern permits must be planned and financed from the start.

Resources and reserves

Public reports about mineral estimates follow codes recognised by CRIRSCO, the Committee for Mineral Reserves International Reporting Standards. CRIRSCO describes itself as a governance system for reporting codes and not a simple template. The organisations aligned with it include JORC for Australasia, CIM for Canada, SAMREC for South Africa, PERC for Europe, SME for the United States and national committees in Brazil, Chile, Colombia, China, India, Indonesia, Kazakhstan, the Philippines, Russia and Turkey, among others. In practice, a company that lists on a major exchange reports its estimates under one of these codes or an equivalent regulation.

The key distinction is between a mineral resource and a mineral reserve. A resource is a concentration of material with reasonable prospects for eventual economic extraction, and its categories, inferred, indicated and measured, reflect rising geological confidence. A reserve is the part of a resource shown by study to be economically mineable once mining, processing, legal, environmental and social factors are taken into account, and it is classed as probable or proved. Many announcements highlight total resource tonnes while saying little about reserves. For investors, the question is how much of a headline number has passed through a study.

The money terms

Governments tax mining through a mix of instruments. Royalties are paid on production or revenue, whether or not the mine is profitable. Corporate income tax applies to profit after deductions. Some countries add a resource rent or windfall tax that bites when prices are high. Others take equity, either free or paid-up, through a state company. Import duties, local content obligations, community payments and withholding taxes on dividends and interest also affect returns.

The International Monetary Fund notes that well-designed fiscal regimes for extractive industries can help developing countries meet their revenue needs while offering investors an attractive return. It also reports that extractive industries account for over 20 percent of government revenues in mining countries. A government that relies on those revenues has a strong reason to change the terms in a price boom, and an investor has an equally strong reason to look for protection.

Stability agreements try to solve this by fixing the tax regime for a number of years, and arbitration clauses give a neutral forum if the state changes the rules. Neither is absolute. Compare the clauses in the contract with what has actually happened to other investors in the same country when prices rose.

Transparency tools

The Extractive Industries Transparency Initiative asks implementing countries to disclose contracts and licences, beneficial owners and the revenues companies pay. Under the 2023 Standard, countries are assessed against it from 1 January 2025. Requirement 2.4 asks multi-stakeholder groups to decide which exploration contracts should be disclosed. Requirement 2.5 encourages a beneficial ownership threshold of ten percent or lower and requires disclosure of politically exposed persons who hold an interest. The Standard also asks for production and export data broken down by project, and encourages the disclosure of proven reserves.

These reports let an incoming company see how much tax comparable mines have paid, who owns the licences it might want to buy and which contracts are public.

Where the production data come from

The U.S. Geological Survey publishes Mineral Commodity Summaries every year. The 2026 edition, dated 6 February 2026, covers more than 90 minerals and materials, with world production, reserves and resources for each. It is a good first source when you want to know which countries produce a metal and how concentrated supply is. It is a summary, so use it for orientation and go to national geological surveys and company filings for detail on a specific country or deposit.

What suppliers and bidders should do

If you sell services to mining, the stage tells you what buyers need. Juniors buy drilling and laboratory work. Developers buy engineering, studies and permitting support. Builders buy equipment, construction and power. Operators buy maintenance, tailings management, water treatment and digital systems. Read the company's latest technical report, check the stage and the date of the study, and ask when the next investment decision is due. A study that is three years old, with cost figures from a different market, is a reason to ask what has been updated.

Guides explain how things generally work. They are not legal, tax or investment advice for a specific project or country. See our editorial policy.