Mining Feasibility Study: Scoping, PFS and BFS Compared
Between a discovery and a mine sit a series of studies, each more detailed, more expensive and more reliable than the last. Here is what a scoping study, a pre-feasibility study and a definitive or bankable feasibility study each involve, how the reporting codes define them, how accurate they are expected to be, and the seven workstreams inside every serious study.
Study stages 3 + PEA
Workstreams 7
Codes JORC · NI 43-101
A mining feasibility study programme moves a project through three main levels of study (scoping, pre-feasibility and feasibility) before anyone commits to build a mine. Each level answers the same question, “can this deposit be mined at a profit, safely and acceptably?”, with more data and more confidence than the last. The final study, often called a definitive or bankable feasibility study (DFS or BFS), is the document lenders and boards use to decide whether to fund construction.
Try it: Feasibility study budget and capex-range calculator →
Project owners, investors and technical teams in Australia, South Africa, Canada and beyond tend to meet the same questions. Below we cover what each study involves, how the JORC Code and NI 43-101 define them, typical accuracy ranges, the seven workstreams, and the mistakes that sink studies. We also show where satellite mineral detection fits at the very start, before the first study dollar is spent. If you are looking at a project as an investor, our overview of gold mining investment routes and the checks to run puts studies in that wider context.
This article explains mining studies in general terms. It is not engineering, legal or investment advice, and it does not replace the reporting code, listing rules and Competent or Qualified Person requirements that apply to your project. Farmonaut is a satellite data-analytics company; we do not prepare feasibility studies or act as a Competent or Qualified Person.
“Mines that started production in 2020–2023 took almost 18 years on average from discovery.” (S&P Global Market Intelligence)
What a mining feasibility study is, and why there are several
A mining feasibility study is a technical and economic evaluation of whether a mineral deposit can be developed into a mine. Geology, mining engineering, processing, infrastructure, environmental and social work, costs and finance all go into one assessment. No project goes straight to a full study, because the cost and time of a detailed one only make sense once cheaper, earlier studies have shown the project deserves it.
So the industry runs a mining feasibility study programme in stages. Each narrows the options, adds data and tightens the cost estimate, and a project can stop at any stage if the numbers don’t work. That saves money that would otherwise go on a detailed study of a weak project. Think of each stage as a gate: pass it, and you earn the right to spend more.
How long it takes
Studies and permitting are a big part of why mines take so long, and a finished mining feasibility study is no promise of a quick start. S&P Global’s lead-time research found an average of 15.7 years from discovery to production across 127 mines. Its follow-up found that mines started between 2020 and 2023 averaged almost 18 years, driven by longer exploration, permitting and study phases and a longer gap between finishing feasibility studies and starting construction. For projects that have completed studies but are not yet operating, a July 2026 S&P Global analysis reports the timeline stretching to nearly 30 years, mostly because of permitting delays. S&P revisits these numbers every year or two, so check for a later cohort.
A study can only be as good as the geology underneath it. The usual reason a feasibility study disappoints is not a spreadsheet error but a resource model built on too few, poorly placed holes. The cheapest time to fix that is before the first study begins.
Scoping, pre-feasibility and mining feasibility study stages compared
The terms vary a little between reporting codes and companies, but the mining feasibility study sequence is consistent. The table compares the main stages. Accuracy ranges are typical figures quoted by industry sources; real targets depend on the company, the commodity and the study’s scope.
| Stage | Purpose | Typical accuracy | Resource basis | Main output |
|---|---|---|---|---|
| Scoping study / PEA | Order-of-magnitude test: is a PFS justified? | About ±30–50% | Can include Inferred Resources, with cautionary statements | Concept, rough economics, go/no-go for PFS |
| Pre-feasibility study (PFS) | Compare options; pick the preferred mining and processing method | About ±20–30% | Measured and Indicated for reserves | Preferred case; first Ore / Mineral Reserve |
| Feasibility study (FS / DFS / BFS) | Detailed study of the selected option to support a development decision | About ±10–15% | Measured and Indicated for reserves | Basis for the decision to build and finance |
How sure can you be of the capital number at each stage? The AusIMM Bulletin puts scoping accuracy at about 30–35%, with some companies accepting ±50%, and AMC Consultants gives 30–35% for scoping and 20–25% for a PFS. Other published summaries give 40–50%, 20–30% and 10–15% for the three stages. The spread between sources is itself useful information: nobody promises a precise figure, and achieved accuracy is often worse than the target.
Mining scoping study (and the NI 43-101 PEA)
A mining scoping study is the first economic test. The JORC Code (2012 edition) defines a Scoping Study as an order-of-magnitude technical and economic study of potential viability, detailed enough to show that moving to a pre-feasibility study can be reasonably justified. In Canada the closest equivalent under NI 43-101 is the preliminary economic assessment (PEA): a study, other than a pre-feasibility or feasibility study, that includes an economic analysis of the potential viability of mineral resources.
Scoping studies and PEAs may use Inferred Resources, but only with prescribed warnings. CSA Staff Notice 43-307 sets out how PEAs are treated, and a PEA that includes Inferred Resources must state, with equal prominence, that it is preliminary, that Inferred Resources are too speculative geologically to be categorised as Mineral Reserves, and that there is no certainty the results will be realised.
Mining prefeasibility study (PFS)
The pre-feasibility study is where options are compared and narrowed; in prefeasibility study mining practice this is usually the longest stretch of engineering judgement. The JORC Code describes a Pre-Feasibility Study as a comprehensive study of a range of options, at a stage where a preferred mining method or pit configuration is established and an effective processing method is determined. It must be enough for a Competent Person to decide whether all or part of the Mineral Resource can be converted to an Ore Reserve. Mining pre feasibility studies are often the first point at which a project can report reserves. Typical quoted accuracy is around ±20–30%. You will also see a mining pre feasibility study written without the hyphen; it is the same thing.
Definitive feasibility study in mining (DFS / BFS)
The JORC Code defines a Feasibility Study as a comprehensive technical and economic study of the selected development option, with appropriately detailed assessment of the Modifying Factors and detailed financial analysis. Its results may reasonably serve as the basis for a final decision by a proponent or financial institution to proceed with, or finance, the project. That last clause is why mining companies call it a definitive feasibility study or a bankable feasibility study, and why “BFS” is common shorthand in mining. The usual target accuracy for this final mining feasibility study is about ±10–15%.
What a study costs
Study costs vary widely with project size, commodity and location, and there is no reliable single figure. One commonly cited estimate puts a detailed feasibility study at about 0.5–1.5% of the total estimated project cost. We found no equally consistent figure for scoping or pre-feasibility budgets, so the calculator below only prices the final study. Treat any number as the start of a conversation with your engineering consultants, not a budget.
Feasibility study budget and capex-range calculator
Assumptions: illustrative arithmetic only, not a quote or engineering advice. Study budget = project cost × the share you enter; the commonly cited range for a detailed feasibility study is 0.5–1.5% of total estimated project cost, and the tool also shows both ends of that range. The capex range applies the ± accuracy of your current stage symmetrically; real estimates are often skewed upward and achieved accuracy is often worse than the target. Accuracy bands come from AusIMM, AMC Consultants and published summaries. Excludes drilling, metallurgical test work, environmental baselines and permitting costs, which are often budgeted separately. Get quotes from study consultants.
Set a US$400 million project at scoping accuracy and the band is hundreds of millions wide. A study costing a few million that halves that band is cheap by comparison, which is the whole economic case for doing the stages properly. If the study itself still needs funding, our guide on where to meet mining investors and what they check covers that raise.
What makes a bankable feasibility study for mining projects
“Bankable” is not a formal category in the reporting codes. It is shorthand for a feasibility study that lenders, and their independent engineers, are willing to rely on when deciding to fund construction. A bankable feasibility study for mining projects is judged less by its title than by its quality and completeness.
- ✔ Reserves, not just resources: a code-compliant Ore or Mineral Reserve, with enough mine life to repay debt with a margin.
- ✔ Engineering to the right depth: designs and quotes detailed enough to support cost estimates at feasibility-level accuracy.
- Proven metallurgy: test work on representative samples, supporting the recovery assumed in the model.
- Independent review: lenders usually appoint an independent engineer to check the study.
- 📊 Environmental and social standards: many lenders apply the Equator Principles to project finance where total project capital costs are US$10 million or more, and with them the IFC’s eight Performance Standards.
- ⚠ Permits and title: a clear path to the mining right and key permits, verified against the official register.
A mining feasibility study that meets the code definition of a Feasibility Study is not automatically bankable, and a definitive study labelled “bankable” still has to pass review. A lender may also be comfortable funding on a well-prepared study that doesn’t use the label. The test is whether the study removes enough uncertainty for the money being asked for. How that money is then layered, from equity to project debt, is set out in how mine projects are funded from licence to mill.
When a company announces a study, look at its level and the resources it relies on. A PEA or scoping study leaning heavily on Inferred Resources is an early signal of potential, not a demonstration of economic viability, and the reporting codes require the company to say so.
Before you commission any study, make sure your drilling is going to the right places. Map your project on mining.farmonaut.com: Map Your Mining Site, or send your licence coordinates through our mining query form for a satellite prospectivity read.
The seven workstreams inside a mining feasibility study
Every mining feasibility study, from scoping to feasibility, covers the same seven workstreams. What changes between stages is the depth of the work and the confidence of the answer. These are the ones that matter most in feasibility study mining work.
1. Geology and resource estimation
The resource model says how many tonnes are there, at what grade, and with what confidence. It is built from drilling, sampling and geological interpretation, and reported under a recognised code (JORC, NI 43-101, SAMREC or S-K 1300) by a Competent or Qualified Person. Classification as Inferred, Indicated or Measured determines what each study level may use.
2. Mining method, design and scheduling
Engineers choose open pit, underground or both, design the layout, and schedule production over the mine life. Modifying Factors (dilution, ore loss, cut-off grade, geotechnical limits) convert resources into reserves.
3. Metallurgy and processing
Test work shows how the ore responds to crushing, grinding, flotation, leaching or other processes, and what recovery to expect. Poor or unrepresentative metallurgical samples cause more late surprises than almost anything else.
4. Infrastructure and logistics
Power, water, roads, rail, ports, accommodation and tailings storage. For remote projects in Africa or Australia, infrastructure can be a large share of the capital cost.
5. Environmental and social impact assessment
Baseline studies of water, biodiversity, air, land use and communities; impact assessment; and management and closure plans. Permitting depends on this work, and lenders test it against international standards.
6. Costs and financial model
Capital and operating cost estimates feed a financial model that produces NPV, IRR, payback and cash flow. For gold, operating cost is often benchmarked as all-in sustaining cost (AISC), the measure set out in World Gold Council guidance.
7. Risk and opportunity analysis
Sensitivity tests on price, grade, recovery, costs and schedule, plus a register of risks and how they will be managed. A good study is candid about what could go wrong.
Some baseline studies need a full year of seasonal data. Started late, they become the critical path for the whole study schedule.
“A PEA using Inferred Resources must say, with equal prominence, that there is no certainty it will be realised.”
Gold mine and iron ore feasibility study examples: what differs
The framework is the same for every commodity. The emphasis is not. Two common search topics show how.
Gold mine feasibility study
A gold mine feasibility study usually concentrates on grade continuity and metallurgy. Gold deposits can be “nuggety”, with grade changing sharply over short distances, so drill spacing and sampling methods matter a lot. Recovery depends on whether the ore is free-milling, refractory or partly oxidised, which decides between gravity, leaching or more complex processing. Economics are often compared using AISC per ounce.
Iron ore feasibility study
An iron ore feasibility study tends to be dominated by scale, product quality and logistics. Bulk commodities must move large tonnages cheaply, so rail, port and shipping costs, and the product’s grade and impurity specification, often decide viability more than the orebody itself.
For both, the earliest question (where exactly is the best mineralisation, and where should the first holes go?) shapes everything that follows. A project that drills its best ground first builds a stronger resource, faster, for the same money.
Why feasibility studies fail, and how to avoid it
A mining feasibility study fails in predictable ways, and the lessons apply to a mining prefeasibility study as much as to a final one. Most problems trace back to rushing early stages or under-investing in data. Nearly all can be avoided with discipline.
- ⚠ Thin geology: too few holes, poorly placed, give a resource that shrinks or shifts when infill drilling arrives.
- Optimistic metallurgy: recoveries based on a few favourable samples rather than representative ore.
- Skipped stages: jumping from a scoping study to a full feasibility study without testing options in a PFS.
- Late ESG work: environmental and social baselines started too late, delaying permits.
- Unrealistic accuracy claims: presenting a scoping-level estimate as if it had feasibility-level precision.
- ⚠ Cost and schedule optimism: underestimating capital, contingency and ramp-up time.
Treating a feasibility study as a sales document backfires. Studies built to reach a target NPV tend to unravel under independent review. The most valuable study is an honest one that tells the board and the lenders what the project really is, weaknesses included.
Planning a feasibility study for mining projects: team, sequence and scope
A study is a project in its own right, with a budget, a schedule and a team, and planning it well is one of the best ways to control cost. The points below apply whether you are commissioning a scoping study, a mining pre-feasibility study run by consultants, or a full definitive study that lenders will review.
Assemble the right team
Most owners appoint a lead engineering consultant to manage the study and integrate the workstreams, with specialists for geology and resources, geotechnics, metallurgy, hydrogeology, environment and social, and infrastructure. The Competent or Qualified Person who will sign off the resource and reserve should be involved from the start, not brought in at the end. A small, experienced owner’s team keeps the consultants aligned and makes the key decisions.
Sequence the work
- Close the data gaps first: infill drilling, geotechnical holes and metallurgical samples usually take longest, so start them before the main study.
- Start environmental baselines early: seasonal data can take a full year to collect.
- Fix the design basis: agree throughput, product, key assumptions and price decks before engineering starts.
- Run options early, then lock them: in a PFS you compare options; in a feasibility study, reopening them wastes time and money.
- Review before release: an internal or independent review before publication catches errors that would otherwise surface in lender due diligence.
Match the scope to the decision
Each mining feasibility study should be scoped to the decision it must support. A scoping study only needs to show whether a PFS is justified, so keep it quick and cheap. A PFS must pick a preferred option and support a first reserve. A feasibility study must support a build-and-finance decision, so its engineering, costing and ESG work have to meet lender expectations. Over-scoping an early study wastes money; under-scoping a late one wastes time when lenders send it back.
Report it correctly
Listed companies must report mining feasibility study results under their exchange’s rules and reporting code: the JORC Code in Australia, NI 43-101 in Canada, SAMREC in South Africa and S-K 1300 in the United States. These set out what can be disclosed at each study level, which resource categories can be used, and the cautionary statements required. Getting disclosure wrong can lead a regulator to demand a retraction, which damages credibility with investors. Private funds read studies the same way; see how mining private equity and VC funds pick projects.
The quickest study schedules are not the ones that rush the study. They are the ones that began the slow data-gathering work (drilling, metallurgical sampling and environmental baselines) early enough that the study never waits for it.
Where satellite mineral detection fits before the first study
Satellite analysis is not a mining feasibility study, and it cannot replace drilling or a code-compliant resource. Its value comes earlier: it helps a project decide where to explore and drill, so the resource that every later study depends on is built on the best ground. Our satellite-based mineral detection analyses multispectral and hyperspectral imagery for the spectral signatures of minerals and alteration, and flags likely mineralised zones, alteration halos, faults and fractures before field teams deploy.
- ✔ Input: the licence coordinates, KML/KMZ or polygon, plus the country and target mineral.
- ✔ Speed and cost: timelines from months to days and up to 80–85% lower early-exploration cost, with reports in 5–20 business days.
- Deliverables: high-potential zones, prospectivity heatmaps, estimated location and depth ranges, geological interpretation, and PDF plus georeferenced GIS files.
- Premium+: TargetMax™ Drilling Intelligence adds recommended drilling angles and interactive 3D subsurface models, helping plan the drilling that a resource estimate, and later a study, relies on.
- ⚠ Limits: satellite targets are exploration targets, not Mineral Resources. They must be tested by fieldwork and drilling before they feed any study.
Satellite screening involves no ground disturbance. Focusing early drilling on the strongest targets cuts the number of drill pads, access tracks and cleared areas, which gives a head start on the environmental footprint every feasibility study must later assess.
See a typical deliverable in our satellite-driven 3D mineral prospectivity mapping overview. We have scanned 100,000+ hectares for 20+ mineral types across 25+ countries. If you are also checking title, our mining cadastre portal guide by country lists the official licence registers.
Build your study on the best ground from the start.
Send us your licence boundary and target mineral. We’ll return ranked target zones, geological interpretation and GIS files in 5–20 business days, so your drilling, and every study after it, starts in the right place.
Frequently asked questions
What is a mining feasibility study?
It is a technical and economic evaluation of whether a mineral deposit can be developed into a profitable, permittable mine. The JORC Code defines a Feasibility Study as a comprehensive study of the selected development option, detailed enough to serve as the basis for a decision to proceed with, or finance, the project.
What is the difference between a scoping study, PFS and DFS?
A scoping study (or PEA in Canada) is an order-of-magnitude test of whether further study is justified. A pre-feasibility study compares options and selects the preferred method, and is often the first basis for reserves. A definitive feasibility study examines the selected option in detail to support a development decision. Accuracy improves at each stage.
What does BFS mean in mining?
BFS stands for bankable feasibility study: a feasibility study of enough quality and completeness for lenders to rely on when funding construction. “Bankable” is not a formal code category; it describes a study, usually reviewed by an independent engineer, that meets lenders’ technical, environmental and social requirements.
Is a mining pre feasibility study the same as a PFS?
Yes. “Pre feasibility”, “pre-feasibility” and “prefeasibility” are spellings of the same stage. It compares mining and processing options, picks the preferred one and is often the first study that can support an Ore or Mineral Reserve. Typical quoted accuracy is about ±20–30%.
Can a scoping study use Inferred Resources?
Yes, with conditions. Under NI 43-101, a PEA may include Inferred Resources if it states, with equal prominence, that it is preliminary, that Inferred Resources are too speculative geologically to be categorised as reserves, and that there is no certainty the results will be realised. Other codes have similar requirements.
How accurate is a mining feasibility study?
Typical targets quoted by industry sources are about ±30–50% for scoping studies, ±20–30% for pre-feasibility studies and ±10–15% for feasibility studies. Achieved accuracy is often worse, especially for mining and infrastructure costs.
Can Farmonaut prepare a feasibility study?
No. We don’t prepare scoping, pre-feasibility or feasibility studies, and we don’t act as a Competent or Qualified Person. We provide satellite-based mineral detection that helps target early exploration and drilling, the work that later studies depend on.
Reviewed September 2026 against the JORC Code 2012 and its linked-data definitions, CSA Staff Notice 43-307 on preliminary economic assessments, the AusIMM Bulletin and AMC Consultants on study accuracy, S&P Global Market Intelligence’s lead-time and July 2026 permitting research, the Equator Principles and the World Gold Council’s AISC guidance.
This article is general information about mining studies. It is not engineering, legal or investment advice. The calculator is illustrative arithmetic on your own inputs. Accuracy ranges vary between sources and timelines come from S&P Global Market Intelligence. Always apply the reporting code, listing rules and professional standards relevant to your project. Satellite results are exploration targets, not Mineral Resources or Reserves.
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