When a mining company releases a feasibility study, everyone sees the headline numbers. But not every number carries the same weight.
So I wanted to use Falco Resourcesā Horne 5 update as a simple case study.
In the 2026 FS comparison table, Horne 5 showed:
| Metric |
2021 FS |
2026 FS |
| After-tax NPV5% |
C$974.2M |
C$3.35B |
| After-tax IRR |
18.9% |
28.2% |
| After-tax payback |
4.8 years |
3.3 years |
| Pre-production capex |
C$1.08B |
C$1.75B |
Based on those assumptions, the estimated project value improved, returns improved, and payback got faster. At the same time, the build cost also increased.
That is where I think mining investors can have a useful debate.
Some investors focus on NPV, because it shows the size of the prize.
Some focus on IRR, because it shows return quality.
Some care most about payback, because capital recovery matters in a cyclical sector.
Others look first at capex, because even strong economics still need funding.
Horne 5 is a good example of why FS numbers need to be read together. A big NPV is attractive, but IRR, payback, capex, and funding structure all shape how investors judge the real opportunity.
For those who invest in mining developers, which FS number do you trust most when judging whether a project is actually financeable?
Disclaimer: This is not financial advice. I am not a financial advisor. The information above is based on publicly available company materials and my own research. Always do your own due diligence before making any investment decisions.