Stages of mineral exploration
The stages of mineral exploration, step by step
Published by Lannister Mining Last updated November 2026
The stages of mineral exploration run from target generation and sampling through trenching and drilling to a formal mineral resource estimate and economic studies.
This page, published by Lannister Mining as part of its Montana gold exploration guide, walks through each stage in order, explains what happens and why it matters, and shows where the Basin Gulch Property sits: past historical drilling and trenching, and working toward a Maiden Mineral Resource Estimate.
What are the stages of mineral exploration?
Most projects follow the same sequence: pick a target, secure the ground, map and sample it, trench and drill it, estimate a resource, then study whether mining it could make economic sense. Each stage costs more than the last, so the results of one stage decide whether the next is funded.
Projects can skip ahead when earlier work already exists. Basin Gulch is one of those, because historical drilling and trenching were completed before Lannister Mining's programs.
The stages in order
Target generation
Geologists choose areas with promising geology, often in known districts or near past producers.
Land acquisition
The company secures mineral rights through patented land, unpatented claims, leases, or options.
Mapping and surface sampling
Rock, soil, and stream samples and geological mapping narrow down where metal is concentrated.
Geophysics and geochemistry
Surveys detect buried structures or alteration that surface sampling cannot see.
Trenching
Shallow excavations expose bedrock so it can be sampled continuously across a target.
Drilling
Drill holes measure grade and thickness at depth; this is where most exploration money goes.
Mineral resource estimate
A qualified person turns drill data into a reportable resource under S-K 1300 or NI 43-101.
Economic studies and permitting
Preliminary economic assessment, prefeasibility, and feasibility studies, alongside permitting.
| Stage | Status at Basin Gulch | Source of the status |
|---|---|---|
| Target generation | Complete | Located in the historic Philipsburg Mining District |
| Land acquisition | Complete | 11 patented and 53 unpatented claims, 1,107 hectares |
| Trenching | Historical work completed | Published trench highlights for gold and silver |
| Drilling | Historical work completed; more planned | More than 320 historical holes; confirmation drilling planned |
| Mineral resource estimate | Planned | Future Maiden Mineral Resource Estimate |
| Economic studies | Not started | Would follow a resource estimate |
What is a drill-stage project?
A drill-stage project is one where drilling, rather than surface work, now drives decisions. Basin Gulch is a drill-stage gold and silver property: Lannister Mining's next steps are expansion and confirmation drilling of historical intercepts and drilling of additional target areas.
Drill-stage projects carry less geological uncertainty than grassroots ground, because metal has already been intersected at depth. They still carry the uncertainty of confirming historical work and defining a resource.
How long does each stage take?
Timing varies widely by project, funding, and permitting, and moving from discovery to production often takes a decade or more. Surface stages can take a field season or two; drilling programs and resource work take longer.
This guide does not publish a timeline for Basin Gulch. For the company's current plans, see the investor presentation on the Lannister Mining website.
Full project details live on the Lannister Mining website
Property maps, team biographies, and the June 2026 USA Investor Presentation for the Basin Gulch Project.
Common questions
Short answers from the full gold exploration FAQ.
What are the stages of mineral exploration?
Mineral exploration usually moves through target generation, prospecting and mapping, sampling and geophysics, trenching, drilling, resource estimation, and economic studies before any development decision. Each stage costs more than the last, so results at one stage decide whether the next is funded. Basin Gulch already has historical drilling and trenching.
What stage is the Basin Gulch Property at?
Basin Gulch is a drill-stage exploration property with extensive historical drilling but no current mineral resource estimate. Lannister Mining plans expansion and confirmation drilling of historical intercepts, aiming for a future Maiden Mineral Resource Estimate. Future drilling is also planned on additional mineralized target areas within the property.
How long does mineral exploration take?
Mineral exploration commonly takes years, and moving from discovery to production often takes a decade or more, depending on the deposit, permitting, and funding. Timelines vary widely between projects. Basin Gulch begins with data from more than 320 historical drill holes, which gives later programs a large existing record to build on.
Why is drilling the most important exploration stage?
Drilling is the only direct way to sample rock at depth and measure grade and thickness. Surface work can point to a target, but drill core or cuttings provide the data used in resource estimates. That is why the more than 320 historical holes at Basin Gulch are central to Lannister Mining's plans.
What is trenching in mineral exploration?
Trenching means digging a long, shallow excavation across a target so geologists can map and sample bedrock continuously. It costs less than drilling and shows how mineralization behaves at surface. Basin Gulch has published trench highlights, including 5 g/t Au and 54 g/t Ag over 34 meters, according to Lannister Mining.
What happens after a mineral resource estimate?
After a resource estimate, companies typically commission economic studies, such as a preliminary economic assessment, followed by prefeasibility and feasibility studies. Metallurgical testing, environmental baseline work, and permitting run alongside. Lannister Mining's stated focus today is further exploration and resource development at Basin Gulch.
Keep reading the guide
- MontanaMontana gold exploration history, the Philipsburg Mining District, and the jurisdiction.
- Basin GulchLand package, access, geology, and exploration upside at the Basin Gulch Property.
- DrillingHistorical drill intercepts and trench highlights from Basin Gulch, explained.
- CompaniesCriteria for evaluating gold exploration companies, with a published-facts comparison.
- USA explorationMineral exploration in the USA, S-K 1300, NI 43-101, and land tenure basics.
- Investors and partnersA briefing on Basin Gulch for investors and exploration partners.
- By the numbersKey gold exploration numbers with sources, as of 2026.