The Ballinalack project is a joint venture between Group Eleven (60% interest) and Shenzhen Zhongjin Lingnan Nonfemet Company Limited (40% interest), one of the largest zinc producers in China, and is located in Counties Westmeath and Longford, north-east Ireland. The property contains what is believed by the Company to be the second largest undeveloped zinc-lead occurrence in Ireland, after Glencore plc’s Pallas Green deposit, and is located approximately 50km west from the currently producing Navan Zinc-Lead Mine (Boliden AB).
Property Geology, Seismic Surveys and Historic Drilling at the Ballinalack Project
The Ballinalack zinc-lead project hosts a compliant NI 43-101 Inferred Mineral Resource of 5.4 million tonnes grading 8.7% Zn+Pb combined (7.6% zinc and 1.1% lead) and 9.0 g/t silver. The resource estimate was prepared by CSA Global (UK) Ltd. (“CSA Global”) under contract to SLR Environmental Consulting (Ireland) Ltd. (“SLR”) and was based Group Eleven’s 2018 drill program, as well as, historic drilling from the 1970s onwards.
- The resource extends over an area of 1600m by 650m, interpreted to sub-crop (near-surface) on the southern end and dip to the north at 15 degrees reaching a maximum depth of 260m;
- Maximum thickness of the resource is estimated at 100m, located in the deepest, northern-most part of the resource;
- Grade generally increases with depth, ranging from 5.1% Zn and 0.5% Pb in the upper horizons, to 11.2% Zn and 2.3% Pb in the lowest horizons;
- Mineralization is mildly affected by folding and faulting;
- Hosted in sulphide mineralization which appears to be related to low temperature hydrothermal processes and which infills stromatactis cavities and has undergone subsequent brecciation;
- It is argued that mineralising processes were related in time to a regional igneous vent, evidenced by tuff bands overlying the mudbank sediments;
- Mineralogy consists of a conventional mixed sulphide assemblage containing pyrite and sphalerite with minor galena and other sulphide minerals;
- Metallurgical testwork indicated that the mineralization would respond well to a conventional froth flotation separation treatment and was also amenable to pre-concentration by dense medium separation.
Note that significant data compilation, re-drilling, re-sampling and data verification may be required by a Qualified Person before the historical estimate can be verified as a current resource. A Qualified Person has not yet undertaken sufficient work to classify the historical estimate as a current resource and the Company is not treating the historical estimate as a current resource. It is estimated that more than $30 million has been invested to date on the Project, which has been subject to a total of 93,350 metres of drilling, including 29,400 metres by the previous operator, Teck Ireland Ltd.
Pale Beds mineralization is known in the Ballinalack area, at several different stratigraphic levels within the Pale Beds. It is best developed in the Bird’s Eye Micrite and Upper (Calcareous) Sandstone. The best mineralised intersections in the Pale Beds are in the footwall of the Ballinalack Fault; importantly, the Pale Beds of the immediate hanging wall have not been tested. Teck Ireland Ltd. intersected low-grade sphalerite-dominated mineralisation in the Pale Beds Bird’s Eye Micrite – 7.6m averaging 0.4% Zn including 2.8 metres averaging 1.2% Zn (Teck, 2008) a meaningful distance away from the Ballinalack Fault.
Plan view of the historical estimate and key intercepts at the Ballinalack Project, Ireland
The potential of the Pale Beds immediately below the Waulsortian-hosted mineralization as a host for a significant zinc-lead mineralization has been largely ignored by previous explorers. Historical drilling overwhelmingly focused on the potential for Waulsortian hosted mineralization. There has also been very little follow-up drilling at the footwall Pale Beds, in the immediate footwall zone of the Ballinalack Fault, despite these being highly mineralized. It should be noted that at Navan (the largest zinc mine in Europe), mineralization is hosted in the Pale (Navan) Beds in the footwall of a major fault. An opportunity exists to conclusively test the Pale Beds horizon (believed to be analogous to the Pale Beds hosting the large Navan zinc-lead deposit). Additional opportunity exists via resource definition drilling and testing regional targets. Significant historic drill intercepts include:
|Gr x Th*
(% x m)
* m% = (Zn+Pb)% multiplied by thickness (m); ^ Dip (degrees from horizontal, from collar dip to largest deviation from collar dip, if known); It should be noted that the mineralization varies in morphology across the deposit, with a strong sub-vertical element close to the Ballinalack Fault, therefore to calculate true thickness it is necessary to multiply the intervals given above by between 0.60 and 0.95. Detailed modelling of the mineralisation, using 3D software, will be necessary to accurately estimate true thickness for each individual intercept. Historic drill results have not been verified by a qualified person as the samples forming the basis of such results are not available to the Company and accordingly no quality assurance programs or quality control measures were applied by the Company.
Cross-section through the Ballinalack historical estimate, showing Pale Bed target
Scientific and technical information in set out in this website has been approved by John Barry, who is a Qualified Person for the purposes of National Instrument 43-101 and who is the Vice President, Exploration Strategy of the Company