Historical Drillhole BUDD192 Shows 29.5m @ 0.8% Cu, 7.5% Pb at Minbrie
Lincoln Minerals has uncovered significant copper and base metals mineralisation in previously overlooked footwall sequences at its Minbrie prospect on South Australia's Eyre Peninsula, prompting a focused two-phase exploration program.
- Historical drillhole BUDD192 confirms copper-lead-zinc-silver mineralisation in footwall Katunga Dolomite
- Previous exploration focused solely on magnetite, leaving base metals largely untested
- Lincoln Minerals reviewing 263 historic drillholes over 12km strike to refine targets
- Two-phase exploration plan initiated: relogging and sampling followed by targeted drilling
- Minbrie prospect situated in highly prospective Gawler Craton region with IOCG analogues
A New Chapter for Minbrie’s Base Metals Potential
Lincoln Minerals Limited (ASX: LML) has announced a compelling development at its Minbrie copper and base metals prospect, located on South Australia's Eyre Peninsula. A detailed review of historical drilling data has revealed significant copper, lead, zinc, and silver mineralisation hosted within the footwall Katunga Dolomite sequence, a zone that was largely overlooked in previous exploration efforts.
The standout discovery comes from drillhole BUDD192, originally drilled by Centrex Metals in 2011, which intersected 29.5 metres grading 0.8% copper, 7.5% lead, 1.9% zinc, and 9 grams per tonne silver starting from 131.1 metres depth. This mineralisation lies beneath the magnetite-bearing Banded Iron Formation (BIF) that was the primary focus of earlier drilling campaigns.
Historical Oversights and New Opportunities
Centrex’s exploration rights were limited to iron ore, leading to a concentrated effort on magnetite within the BIF and a systematic under-sampling of the footwall sequence. Many drillholes either terminated shortly after intersecting the BIF or were not assayed for copper and base metals due to the absence of visible magnetite. This has left a substantial and largely untested copper and base metals target zone spanning over 12 kilometres of strike.
Lincoln Minerals, which holds rights to all other metals on the tenement, acquired the historical drillhole data and core samples from Centrex in 2018. The company is now leveraging this extensive database, comprising approximately 263 drillholes, alongside geochemical and geophysical datasets to refine exploration targets and unlock the true potential of the Minbrie prospect.
Strategic Two-Phase Exploration Program
To systematically evaluate this opportunity, Lincoln has initiated a two-phase exploration program. Phase 1 involves relogging and geochemical sampling of historical drillholes, including portable XRF analysis and laboratory assays for base and precious metals. This phase also includes analysis for associated elements such as gallium, iridium, germanium, and rare earths, which have been identified in other Eyre Peninsula base metal deposits.
Phase 2, contingent on Phase 1 results, will consist of targeted drilling to extend mineralisation around BUDD192 and test newly identified zones along the strike and down dip. This approach aims to fill the gaps left by previous magnetite-focused drilling and to delineate the extent of copper and base metals mineralisation in the footwall sequence.
Regional Context and Geological Significance
The Minbrie prospect lies within the Gawler Craton, a geologically stable and mineral-rich region known for hosting world-class iron oxide-copper-gold (IOCG) deposits such as Olympic Dam, Prominent Hill, and Carrapateena. The prospect’s proximity to significant base metal occurrences, including the Paris Silver-Lead and Menninnie Dam Lead-Zinc-Silver deposits, underscores its potential.
Geological analysis indicates that the footwall rocks at Minbrie, including dolomite, calc-silicates, and graphitic sequences, are highly reactive lithologies conducive to metasomatic and hydrothermal mineralisation processes. The presence of the Hiltaba Granite within 15 kilometres further aligns Minbrie with regional mineralising events linked to the Hiltaba Event (circa 1595-1575 million years ago), which is associated with major IOCG systems.
Looking Ahead
Lincoln Minerals’ CEO Jonathon Trewartha emphasised the significance of this underexplored footwall sequence, stating that the company is well-positioned to advance Minbrie’s base metals potential by integrating historical data with modern exploration techniques. With regulatory and land access approvals underway, the company is poised to accelerate its exploration activities in the coming months.
This renewed focus on Minbrie could redefine Lincoln Minerals’ asset portfolio and contribute meaningfully to the copper and base metals supply outlook from South Australia’s Eyre Peninsula.
Bottom Line?
Lincoln Minerals is set to unlock Minbrie’s hidden base metals potential, with exploration results poised to reshape its growth trajectory.
Questions in the middle?
- Will Phase 1 assays confirm the extent and grade of copper and base metals in the footwall sequence?
- How extensive is the mineralisation along strike and at depth beyond drillhole BUDD192?
- What impact could new discoveries at Minbrie have on Lincoln Minerals’ valuation and development plans?
