Improving Mineral Exploration Through Historical Databases and Drilling Data

Precious Metals

Mineral exploration efforts are being optimized by historical databases that are helping to inform mining and exploration companies.

Historical databases have proven to be an effective means of advancing mineral exploration activities.

Compiling, analyzing and interpreting data is critical to the success of an exploration project. Early exploration often involves geophysical surveys and geochemical sampling to find new discoveries. When determining a resource model for any given deposit, proper drill placement is essential to returning high-quality assay results.

When it comes to generating news flow and building stock momentum, favorable assay results are the life force of any junior exploration company. This type of data can go a long way toward de-risking the project for investors. Missing the mark and producing bad drill results can be highly-damaging to investor confidence and ultimately the company’s share price.

The knowledge generated by previous operators takes out a lot of the guesswork and risk for resource companies in their search for new deposits.

Mineral exploration and historical databases

The early stages of mineral exploration are some of the longest and most inherently risky phases in the lifecycle of a mine. While some geological teams will be starting from scratch, many companies have the good fortune of acquiring projects with a historical database of past exploration work, including soil sampling, geophysical surveys and even core samples. Sometimes these properties have been through multiple drill campaigns by different operators going back decades. Hence, such databases can provide junior exploration companies with significant leverage when it comes to quickly and cost-effectively identifying resources and advancing a project toward development.

In fact, there are many junior exploration companies that choose to target previously explored properties with access to historical databases that can easily be re-evaluated and validated with new exploration techniques.

Historical data is not considered compliant with current industry reporting standards. The mining industry’s two current and most commonly used standards of disclosure for mineral projects are Canada’s National Instrument 43-101, established in 2001, and Australia’s JORC Code, established in 1989. If the database predates these standards, any information contained in them will need to be validated prior to establishing a resource estimate.

Under NI 43-101 standards, exploration data from work completed after 2001 is still considered historic if the work was completed on a property prior to a change of ownership. However, when a junior company acquires a new project it’s highly likely that the most recent sampling and drilling completed on the property was performed with industry best practices, including quality assurance and quality control (QA/QC). It also means that the results were likely verified by a qualified person (QP) under NI 43-101 standards and documented in a technical report. Original assay certificates may also be available for validation by the new QP.

Junior companies need to keep their costs low and would like to use as much of the available data as is feasible to move the project forward. How can an exploration team use best practices to verify this data and use it to form a reliable investment case for gaining funding for future exploration?

Mineral exploration and validation drilling

Validation drilling is often used to confirm or improve historical drill results. Twinning is one of the most commonly used validation drilling techniques and involves drilling a new hole in close proximity to a historical drill hole collar. If the validation drill results positively correlate with the previous operator’s drill results, the geological team can then confirm their confidence in the historical database.

Reunion Gold’s (TSXV:GRD) recent success at the Nivré deposit, part of the Dorlin gold project in French Guiana, is a good example of validation drilling. The company’s historical data validation program at Nivré began with re-sampling and re-assaying several hundred mineralized core intervals from more than 100 drill holes completed on the deposit in the 1990s.

The re-sampling results correlated well with the historical values, which led Reunion to conduct a validation drilling program that included drilling five holes twinned to historical drill holes. The results of the validation drilling demonstrated that the historical data could reliably be used to produce a NI 43-101 compliant resource estimate on the deposit.

Together with results from extension drilling on the Nivré deposit, the validation drill data led to the company’s March 2019 resource estimate, which is notably similar to the one reported in 1998. The Nivre deposit contains 18.9 million indicated tonnes grading 1.09 grams per tonne (g/t) gold and 26 million inferred tonnes grading 1.06 g/t gold. Reunion’s success with its projects in the Guiana Shield recently earned the company a strategic agreement with Barrick Gold (TSX:ABX,NYSE:GOLD) that includes a 50-50 alliance to collaboratively explore for, develop and mine the projects in the region. Barrick is expected to fund US$4.2 million on these projects, and increase its interest in the company to 19.9 percent.

Vector for discovery

When Silver Viper Minerals (TSXV:VIPR,OTC Pink:VIPRF), a member of the Belcarra Group, acquired the La Virginia gold-silver project in late 2018, the company also gained access to a historical database that included 52,000 meters of drilling over 188 drill holes with the most recent historical holes drilled in 2013. Historically reported high-grade findings from this previous work include a 23.5 meter interval grading at 13.69 g/t gold equivalent.

Located in the Mexican state of Sonora within the mineral-rich Sierra Madre Occidental, La Virginia also shows evidence of small-scale underground mining from the 1970s. More recently, mineralization on the property was first identified during a regional surface mapping and geochemical sampling program conducted by Minefinders in 2007. Minefinders later conducted its drilling program at La Virginia from 2010 through to early 2013. After its acquisition of Minefinders, Pan American Silver (TSX:PAAS,NASDAQ:PAAS) conducted further drilling on the property in 2013. As a result, the historical database for La Virginia is now comprised of 22,553 individual multi-element analyses and fire assay results, all supported by analytical QA/QC.

Silver Viper’s QP reviewed this historical data on the project, including drill cores and historical logging, and found the database reliable enough to use in the planning of its 2018 exploration program at La Virginia. The work included a regional reconnaissance survey that helped the company’s geological team identify prospective areas for drilling. By the end of the 2018 drilling season, Silver Viper had completed 4,753 meters in 20 diamond drill holes over five prospective areas, including drill testing of previously undrilled mineralized showings and validation drilling at the Las Huatas and Con Virginia prospects to test gaps in the historical data.

Silver Viper’s drill work in 2018 also led it to a new discovery at La Virginia. “The discovery was in the El Rubi zone, which had previously not been sampled or mapped because it’s a difficult region to access, but our team was relentless,” Silver Viper CEO Steve Cope told the Investing News Network. “We drilled five holes into one of the identified targets, all of which hit a brand new zone, as well as a parallel zone deeper down. Our feature hit was 13 meters of 6.5 g/t gold equivalent. That’s a great discovery on a brand new target, and it’s got the size potential. We’ve identified that it has the potential to run 2.2 kilometers to the north and an additional kilometer to the south.”

Next steps forward for Silver Viper at La Virginia include continued mapping, sampling and drilling to further show the project’s potential value in the hopes of attracting a major as a partner or purchaser of the project.


Historical databases often represent millions of dollars of invested capital. Access to such data offers companies a clear advantage in de-risking a project at a reduced cost in both time and money. Exploration companies that acquire mineral projects with robust historical databases can leverage the data generated by past investment to unlock potential value for their shareholders as they search for new discoveries.

This article was originally published by the Investing News Network in April 2019.

This INNSpired article is sponsored by Silver Viper Minerals (TSXV:VIPR). This INNSpired article provides information which was sourced by the Investing News Network (INN) and approved by Silver Viper Minerals in order to help investors learn more about the company. Silver Viper Minerals is a client of INN. The company’s campaign fees pay for INN to create and update this INNSpired article.

This INNSpired article was written according to INN editorial standards to educate investors.

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The information contained here is for information purposes only and is not to be construed as an offer or solicitation for the sale or purchase of securities. Readers should conduct their own research for all information publicly available concerning the company. Prior to making any investment decision, it is recommended that readers consult directly with Silver Viper Minerals and seek advice from a qualified investment advisor.

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