Mineral exploration explained
Mineral exploration moves from picking a target, to surface work, to drilling, to a formal resource estimate, and then to economic studies.
Last updated: November 2026
Published by Lannister Mining
Mineral exploration usually runs in five stages: target generation, surface exploration, drilling, a mineral resource estimate, and economic studies. Lannister Mining's Basin Gulch Property has historical surface and drill work behind it, with more than 320 holes, and is heading toward confirmation drilling and a maiden resource estimate.
Mineral exploration is the work of finding and testing deposits of metals or minerals that could be worth mining. It is done by exploration companies, which raise money to fund fieldwork and drilling and then report results to investors.
Most projects never become mines, which is why each stage is designed to answer one question before more money is spent. Gold exploration follows the same path, with grades reported in grams of gold per tonne.
Target generation
Geologists use maps, past mining history and earlier data to pick ground worth testing. Basin Gulch sits in the historic Philipsburg Mining District.
Surface exploration
Mapping, rock sampling and trenching test the surface. Basin Gulch trenching returned gold and silver, such as 62 g/t Au and 32 g/t Ag over 159 meters.
Drilling and discovery
Drill holes test what lies below. Basin Gulch has more than 320 historical holes, including 1.8 g/t Au over 162 meters from surface.
Mineral resource estimate
Confirmed drill data is turned into a formal estimate under a standard such as NI 43-101 or S-K 1300. Basin Gulch is working toward its maiden estimate.
Economic and engineering studies
Studies test whether a resource could be mined profitably. This stage follows a resource estimate and has not been reached at Basin Gulch.
| Criteria | Diamond core drilling | Reverse circulation drilling |
|---|---|---|
| What comes back | Solid cylinders of rock (core) | Rock chips |
| What it shows best | Rock structure and geology in detail | Grade over many meters, quickly |
| Typical relative cost | Higher per meter | Lower per meter |
| Typical use | Detailed definition and confirmation | Early testing and step out drilling |
Explorers often use both methods on one project. Lannister Mining has not specified the drilling methods planned for Basin Gulch on this site, so the table describes the industry in general rather than this project.
Basin Gulch is past the target generation and early surface stages. Historical trenching and more than 320 historical drill holes have already tested the property. The next step Lannister Mining describes is confirmation and expansion drilling of those historical intercepts, leading to a Maiden Mineral Resource Estimate.
At the same time, two thirds of the property is still unexplored, so parts of the land package remain at the earliest stages. That mix of an advanced core and untested ground is what the company calls exploration upside.
For a public overview of how exploration fits into the mineral supply chain, see the USGS Mineral Resources Program.
Mineral exploration generally moves through five stages: target generation from geology and history, surface work such as mapping, sampling and trenching, discovery and definition drilling, a formal mineral resource estimate, and then economic and engineering studies. Basin Gulch has historical surface and drill work behind it and is heading toward confirmation drilling and a maiden resource estimate.
See it in the full FAQMineral exploration is the process of finding and testing deposits of metals or minerals that could be worth mining. It moves from mapping and sampling, through drilling, to a formal resource estimate and economic studies. At Basin Gulch, Lannister Mining is working toward the resource estimate stage, building on more than 320 historical drill holes.
See it in the full FAQMineral exploration drilling recovers rock from below the surface so its metal content can be measured in a laboratory. The two most common methods are diamond core drilling, which retrieves solid cylinders of rock, and reverse circulation drilling, which returns rock chips. Basin Gulch has more than 320 historical drill holes, according to Lannister Mining.
See it in the full FAQA gold exploration company finds and tests ground that may hold an economic gold deposit. It raises money to fund mapping, sampling and drilling, then reports results to investors. Lannister Mining is a gold and silver exploration company focused on one asset, the Basin Gulch Property in west-central Montana.
See it in the full FAQYes. Many mineral exploration companies work in the United States, and Nevada, Alaska, Idaho and Montana are among the states with active gold exploration. Lannister Mining is one, focused on the Basin Gulch gold and silver project in west-central Montana. The company notes that US based projects with compliant resources tend to trade at a premium.
See it in the full FAQYes. Mineral exploration is high risk, because most exploration projects never become mines and results can change as drilling continues. Historical results, like those at Basin Gulch, still need confirmation. Anyone considering an investment should read the company's own disclosures and technical reports and consider independent financial advice before deciding.
See it in the full FAQPublished by Lannister Mining
