A junior miner drops a press release at 7 a.m.: positive study, big after-tax NPV, juicy IRR. The stock gaps up 30% and then bleeds all afternoon. If you trade TSXV and CSE names, you need to understand PEA vs PFS vs feasibility study results. The same headline numbers mean very different things depending on which study produced them. This guide covers what each study is allowed to say under Canadian rules, which numbers to check first, and why a financing so often lands right after the results.
PEA, PFS and feasibility study are the three stages of mining study under Canada’s NI 43-101, ranked by confidence. A PEA is a rough first look that can lean on inferred resources. A PFS picks the development plan and can declare reserves. A feasibility study adds detailed engineering and tighter cost estimates so a company can decide whether to build.
In this article
- What is the difference between a PEA, a PFS and a feasibility study?
- PEA vs PFS vs feasibility study: the comparison table
- Which numbers should you check first in a mining study?
- Why does a financing often follow a mining study?
- How do you read a study press release as a trader?
- FAQ
- What order do mining studies come in?
- How accurate are the cost estimates in each study?
- How much does each study cost and how long does it take?
- More questions traders ask
What is the difference between a PEA, a PFS and a feasibility study?
A PEA is an early, low-confidence economic sketch that can use inferred resources. A PFS is the first study that can turn resources into reserves. A feasibility study is the detailed version a company or lender can use to decide whether to build the mine.
All three are defined in Canada under National Instrument 43-101. The resource and reserve categories come from the CIM Definition Standards, which NI 43-101 incorporates. Each study has to be prepared or supervised by a Qualified Person (QP). When a company first discloses material study results, it generally has to file the full technical report on SEDAR+ within 45 days.
Before trusting any study headline, it helps to know what NI 43-101 compliant actually guarantees about a mining stock, and what it does not.
Think of it as a ladder. Each rung costs more money, takes more drilling and engineering, and narrows the range of outcomes. The headline numbers can go up or down as you climb. Costs, in particular, tend to get more realistic as the engineering gets more detailed.
PEA vs PFS vs feasibility study: the comparison table
| Factor | PEA | PFS | Feasibility study (FS) |
|---|---|---|---|
| Confidence level | Lowest. Conceptual, early-stage | Medium. Preferred mining and processing methods selected | Highest. Detailed engineering on the chosen option |
| Resource categories in the economics | Measured, indicated and inferred | Measured and indicated only | Measured and indicated only |
| Can it declare mineral reserves? | No | Yes (probable and proven) | Yes (probable and proven) |
| What NI 43-101 lets it disclose | Economic analysis that includes inferred resources, but only with the mandatory cautionary statement | Reserves and economics based on reserves; inferred material can’t count toward the economics | Reserves and economics; CIM says it can serve as the basis for a decision to proceed with or finance development |
| Main job | Show the project could work and justify the next spend | Pick the development option and convert resources to reserves | Support a construction decision and project financing |
| What usually comes next | More drilling, a PFS, a raise | An FS, permitting, a raise | Permits, project financing, a build decision |
Resources vs reserves in one minute
Under CIM, a mineral resource is mineralization with reasonable prospects for eventual economic extraction. It is ranked by geological confidence: inferred (lowest), indicated, then measured.
A mineral reserve is the economically mineable part of measured and indicated resources after you apply the modifying factors. Those cover mining, processing, metallurgy, economics, legal, environmental, social and permitting. CIM requires at least a PFS to declare reserves. Indicated resources convert to probable reserves. Measured resources convert to proven reserves, or to probable ones in some circumstances.
That is why the word reserves in a press release is a real step up. A PEA cannot produce reserves, no matter how good the numbers look.
Don’t skip the PEA cautionary statement
NI 43-101 generally bars companies from disclosing economic analysis that uses inferred resources. The PEA is the exception, and it comes with conditions. The company must state that the PEA is preliminary in nature. It must also say that it includes inferred resources considered too speculative geologically to be categorized as reserves, and that there is no certainty the PEA will be realized.
So check how much of the mine plan is inferred. If the early production years mostly come from inferred material, the NPV rests on the lowest-confidence category there is.
US-registered miners follow the SEC’s S-K 1300 rules. They use a similar ladder, with an initial assessment in place of the PEA.
Which numbers should you check first in a mining study?
Start with four numbers: the discount rate, the commodity price deck, initial capex and the payback period. Together they show how much of the headline NPV is real and how much is assumption.
1. NPV and the discount rate
NPV is projected future cash flow discounted back to today. The lower the discount rate, the bigger the NPV. You’ll often see 5% on precious metals studies and 8% or higher on base metals or riskier projects.
Look at the sensitivity table to see the NPV at other rates. Be skeptical of a low rate headlined on an early, high-risk project. Also check whether the headline is pre-tax or after-tax. The after-tax number is the one that matters to shareholders.
2. The commodity price deck
Every study assumes a price for the metal. Compare it to today’s spot price. If the base case sits well above spot, the project is partly a bet on the commodity.
The sensitivity table tells you what happens to NPV and IRR if price drops 10% or 20%. A project that only works at an optimistic price deck is fragile.
3. Initial capex
Initial capex is what it costs to build the mine before first production. Compare it to the company’s market cap and cash.
Hypothetical example: a junior with a $50M market cap publishes a PEA with $500M initial capex. That gap has to be funded with equity, debt, streams, royalties or a partner, and most of those dilute you somehow.
Also check sustaining capex, the contingency allowance, and the accuracy range the report states for its cost estimates.
4. Payback period
Payback is how long the mine needs to earn back initial capex. A short payback means less time exposed to price swings and cost overruns. Check whether it’s measured from the start of production or from the build decision, because the difference can be years.
Once you’ve covered those four, scan the rest:
- After-tax IRR and life of mine
- Mined head grade vs the resource’s average grade (front-loaded high grade flatters early years)
- Metallurgical recovery and how much test work supports it
- Strip ratio and all-in sustaining cost
- Royalties, streams and jurisdiction
Why does a financing often follow a mining study?
A study hands the company a fresh, quantified story right when the stock is strongest. The next step costs money the junior usually doesn’t have.
Pre-production miners have no revenue. More drilling, the next study, permitting and environmental work all burn cash. The cheapest time to raise is when price and volume are up, and that is right after the results land.
Expect to see a bought deal or brokered placement at a discount, sometimes with warrants attached. Exploration-stage names often raise with flow-through shares, which bring their own selling pressure.
Hypothetical example: a junior releases a PEA before the open and gaps up 40%. That evening it announces a bought deal priced well below the day’s high. The next morning the gap fills.
Not every study is followed by a raise. But you can check the odds yourself. Pull the latest financial statements and MD&A on SEDAR+, then compare the cash balance with the planned spending.
How do you read a study press release as a trader?
Work through this checklist before you size anything:
- Which study is it: PEA, PFS or FS? Is it new or an update?
- Is a Qualified Person named?
- What share of the mine plan is inferred?
- What is the discount rate? Is the headline pre-tax or after-tax?
- How does the price deck compare to spot?
- How big is initial capex vs market cap and cash on hand?
- How long is the payback, and from when?
- When is the technical report due on SEDAR+?
- Has a financing been announced, or is the cash balance low?
- If it’s an update, what changed from the previous study and why?
Remember that every study rests on a resource, and every resource rests on drilling. If you can’t judge the holes, start with how to read drill results.
To see this kind of work done on real juniors, read our deep dives on Talon Metals and Scandium Canada. Both are built from filings rather than headlines.
FAQ
Is a PFS better than a PEA?
It is higher confidence, not necessarily better news. A PFS can declare reserves and uses more detailed engineering. That often means the NPV comes in lower than the PEA because costs are better defined.
Can a PEA include inferred resources?
Yes. It is the only NI 43-101 study whose economics can include inferred resources, and it must carry the required cautionary statement when it does.
Why did a mining stock drop after a positive study?
Common reasons include traders selling the news after a run-up, a financing announced on the strength, numbers that missed expectations, or a price deck the market didn’t believe.
Where do I find the full technical report?
Search the company’s profile on SEDAR+. The report is generally due within 45 days of the press release that first disclosed the results.
Does a feasibility study mean the mine will be built?
No. The company still needs permits, financing and a construction decision, and plenty of projects with a completed FS never get built.
What order do mining studies come in?
The usual order is resource estimate, then PEA, then PFS, then feasibility study, then a build decision. Each step reuses and tightens the work from the one before it. Companies can skip a rung, for example going straight from resource to PFS, but they can’t declare reserves without at least a PFS.
- Resource estimate: how much mineralization is there and at what confidence
- PEA (often called a scoping study elsewhere): could this make money at all?
- PFS: which mining and processing option, and how much converts to reserves?
- FS (you’ll also see DFS for definitive or BFS for bankable): detailed engineering on the chosen option
- Build decision: permits, financing and a board vote to construct
DFS and BFS are informal labels. Under NI 43-101 they are all just a feasibility study.
Same ladder, different codes: S-K 1300 and JORC
US and Australian miners climb the same ladder under different names. Under the SEC’s S-K 1300, the stages are initial assessment, pre-feasibility study and feasibility study. An initial assessment plays the PEA role and can’t be used to support reserve disclosure. The supporting document is a technical report summary, filed as an exhibit you can find on EDGAR.
ASX-listed companies report under the JORC Code and use scoping study, PFS and FS. ASX has its own rules for production targets and forecasts that come out of a scoping study, especially when they rely on inferred resources, so look for a cautionary statement near the top of the release.
How accurate are the cost estimates in each study?
Accuracy gets tighter at each stage: a PEA carries the widest range, a PFS is narrower, and an FS is the narrowest. The ranges you see quoted around the industry are conventions, not NI 43-101 rules. Use the accuracy range stated in the specific technical report, usually in the capital cost section, and apply it to the capex yourself to see the plausible high end.
How much does each study cost and how long does it take?
Each stage costs more and takes longer than the last, and the company usually tells you its own budget and timeline. The big cost drivers are infill drilling to upgrade resources, metallurgical test work, engineering detail and, by the FS stage, environmental baseline studies. Drilling seasons, slow lab turnaround and baseline work that has to cover a full year of conditions are what usually stretch the schedule.
Skip the generic estimates online. Pull the latest MD&A and news releases on SEDAR+ and look for the stated budget and target date for the next study. Then compare that budget to cash on hand, and you’ll know whether a raise is likely before the study lands. Our guide on checking dilution on SEDAR+ walks through finding those documents.
Do you need financial modeling software to check study economics?
No. The economic analysis section of the technical report already shows NPV and IRR under different prices, costs and discount rates. Reading those sensitivity tables gets you most of what a model would.
What is the difference between bench-scale and pilot plant test work?
Bench-scale tests run small samples in a lab, while a pilot plant runs a larger, continuous version of the planned process. A pilot plant is a test program that feeds a study, not a study itself. More advanced studies generally rely on more extensive test work, so a recovery figure backed only by early bench tests deserves more skepticism.
More questions traders ask
What is a bankable feasibility study?
It’s industry shorthand for a feasibility study that lenders are willing to finance against. Bankable is not a defined NI 43-101 or CIM category. Lenders typically hire their own independent engineer to review the study before they commit.
How do I find an example technical report on SEDAR+?
- Go to SEDAR+ and search the company name to open its profile.
- Open the documents list and filter or sort by document type.
- Look for the technical report filing, usually dated within the window after the results press release.
- Open the PDF and jump to the summary, capital costs and economic analysis sections.
For worked examples, see how our Talon Metals and Scandium Canada deep dives use the filed reports.
If you want to go through study results, technical reports and the financings that follow with other traders who read the filings first, come join the free Fockets stock trading Discord. Ask questions, share your own read, and do your own work.
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Disclaimer: This post is for educational purposes only and is not financial advice or a recommendation to buy or sell any security. Mining and small-cap stocks are high risk, and you can lose some or all of your money. Do your own research, read the primary filings, and size your own risk before making any trade.
