Exploration guide
The stages of mineral exploration, step by step
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The stages of mineral exploration run from grassroots prospecting to target definition, drilling, resource estimation, economic studies and finally permitting and development.
Each stage of mineral exploration reduces uncertainty and usually costs more than the last. Lannister Mining's Basin Gulch property in Montana shows how a real project moves through them: it already has more than 320 historical drill holes, and its next stated milestone is confirmation and expansion drilling toward a maiden mineral resource estimate.
What stage of mineral exploration is Basin Gulch at?
Basin Gulch is at the drilling and resource definition stage. Historical programs, labeled on the company property map from 1987, 1989 and 1993 through 1997, produced more than 320 drill holes. Lannister Mining now plans to confirm key historical intercepts, expand known mineralization and test new targets, then use that work in a maiden mineral resource estimate.
That puts the project past grassroots exploration but before economic studies or permitting. For investors, this stage often brings the most news flow from drill results, and the most uncertainty about what a final resource will look like.
Procedure
The six stages in order
Not every project passes through every stage cleanly, and most prospects stop early. This is the usual sequence.
Grassroots prospecting
Geologists map rocks, take surface samples and review historical records to find areas worth a closer look.
Target definition
Geophysical surveys, geochemistry and trenching narrow the search to specific drill targets.
Discovery and delineation drilling
Drill holes test targets; successful ones are followed by tighter drilling to outline the mineralized body.
Resource estimation
A qualified person prepares a mineral resource estimate under a reporting standard such as NI 43-101 or S-K 1300.
Economic studies
Preliminary economic assessments, then pre-feasibility and feasibility studies test whether a mine could pay.
Permitting and development
The company secures permits and financing, then builds the mine.
Where does Basin Gulch sit at each stage?
| Stage | Typical work | Basin Gulch status |
|---|---|---|
| Grassroots prospecting | Mapping, rock and soil sampling, reviewing old records | Complete; the property has a long historical record |
| Target definition | Geophysics, trenching, choosing drill targets | Historical trenching done; new targets in unexplored areas |
| Discovery and delineation drilling | Drilling to find and outline mineralization | More than 320 historical holes; confirmation and expansion drilling planned |
| Resource estimation | First formal estimate under NI 43-101 or S-K 1300 | Next milestone: a future maiden mineral resource estimate |
| Economic studies | Preliminary economics, then pre-feasibility and feasibility | Not yet started |
| Permitting and development | Permits, financing, construction | Not yet started |
Definition
What is a mineral resource estimate?
A mineral resource estimate is a formal statement of how much mineralized rock a deposit contains and at what grade, prepared by a qualified person under a disclosure standard. In Canada that standard is NI 43-101; in the US, the SEC uses S-K 1300. Resources are grouped by confidence into inferred, indicated and measured categories.
Lannister Mining has said that historical drilling and new work programs at Basin Gulch will be used in a future maiden mineral resource estimate, and that there is a clear market premium for compliant gold and silver ounces in the USA. Until that estimate is published, historical drill results remain exploration data rather than a resource.
By the numbers
The Basin Gulch starting point
- historical drill holes already completed
- 320+
- historical drill years on the company map: 1987, 1989, 1993 to 1997
- 7
- of claims to explore
- 1,107 ha
- of the property still unexplored
- 2/3
Exploration stage questions
Short answers here. The full mineral exploration FAQ has more.
What are the stages of mineral exploration?
The usual stages are grassroots prospecting, target definition, drilling, resource estimation, economic studies, permitting and, if everything works, development. Each stage reduces uncertainty and usually costs more than the last. Basin Gulch already has historical drilling, and Lannister Mining's next stated goal is confirmation and expansion drilling toward a maiden mineral resource estimate.
What is a maiden mineral resource estimate?
A maiden mineral resource estimate is the first formal estimate of the tonnes and grade in a deposit, prepared under a reporting standard such as Canada's NI 43-101 or the SEC's S-K 1300. Lannister Mining states that historical drilling and new work programs at Basin Gulch will be used in a future maiden mineral resource estimate.
What are NI 43-101 and S-K 1300?
NI 43-101 is the Canadian rule for public disclosure of mineral project information, and S-K 1300 is the US Securities and Exchange Commission's rule for mining property disclosure. Both rely on qualified persons. Lannister Mining's investor page states there is a clear market premium for S-K 1300 and NI 43-101 compliant gold and silver ounces in the USA.
Does Basin Gulch have a current mineral resource estimate?
Not yet. Lannister Mining describes a future maiden mineral resource estimate that will use historical drilling plus new work programs. The company states the property has potential to host a significant maiden estimate after expansion and confirmation drilling of historical intercepts. Until that estimate is published, historical results should be read as exploration data.
What is trenching in mineral exploration?
Trenching means digging a shallow excavation across exposed or near-surface rock and sampling it continuously. It is cheaper than drilling and shows surface geology clearly. Lannister Mining lists trench highlights at Basin Gulch, such as 4 g/t gold and 23 g/t silver over 146 meters, as part of the historical work on the property.
What are the risks of investing in mineral exploration companies?
Exploration is high risk: most prospects never become mines, historical results may not be confirmed, and companies often need to raise more money as they advance. Metal prices, permitting and markets also move values. Basin Gulch has a large historical dataset but no current resource estimate yet, so investors should weigh both facts.