Mineral Resource estimation was completed by
Resource Estimate Criteria
In calculating the resource estimate, WAI used a cut off grade of 3% Zinc equivalent ('ZnEq'). In order to calculate the ZnEq grade, the QP consulted with metallurgists within the WAI team to establish appropriate recoveries to use for the estimate based on prior experience in the Iberian Belt and similar deposits. It is important to note that the recovery factors used in the estimate are not based on metallurgical test data as this work is not yet completed. The metal recoveries are based on representative results from other deposits in the belt. La Romanera is a unique deposit within the Iberian pyrite belt in that a significant portion of the deposit has highly elevated gold values relative to other deposits in the region. As such, there is not a good metallurgical analogy for the recovery of gold from higher grade gold mineralization in the region. The high gold grades are not ubiquitous throughout the deposit such that the overall gold grade reported represents a weighted average of higher grade and lower grade mineralization. For the ZnEq calculation, the gold recovery factor used was 20%. An important opportunity and challenge for the Company will be to work with its metallurgical consultants to improve the gold recoveries from the gold enriched portions of the deposit. Such an improvement could positively add to the ZnEq grade and tonnage at La Romanera.
Resource Highlights:
Iberia Belt West Initial Mineral Resource Estimate ('MRE') Indicated 14.07 million tonnes ('MT') grading 3.29% Zn, 1.66% Pb, 0.46% Cu, 75.2 g/t Ag and 1.39 g/t Au (7.63% ZnEq)
Inferred 4.71 MT grading 4.70% Zn, 2.14 % Pb, 0.54% Cu, 72.4 g/t Ag and 0.90 g/t Au (9.29% ZnEq)
La Romanera
Indicated 13 MT grading 2.98% Zn, 1.45% Pb, 0.42% Cu, 74.1 g/t Ag and 1.48 g/t Au (7.08% ZnEq)
Inferred 3.14 MT grading 4.85% Zn, 1.96 % Pb, 0.45% Cu, 71.3 g/t Ag and 1.16 g/t Au (9.16% ZnEq)
The La Romanera mineral resource estimate was calculated using data from 144 holes comprising 52,750 meters of drilling.
La Infanta
Indicated 1.07 MT grading 7.10% Zn, 4.24% Pb, 1.03% Cu 88.5 g/t Ag and 0.32 g/t Au (14.32% ZnEq)
Inferred 1.56 MT grading 4.41% Zn, 2.49% Pb, 0.74% Cu, 74.7 g/t Ag and 0.38 g/t Au (9.55% ZnEq)
The La Infanta mineral resource estimate was calculated using data from 86 holes comprising 19,565 m of drilling.
Mineralization remains open at both deposits
The MRE confirms the resource starts at or near surface and remains open for expansion at depth and along strike.
Next steps
La Romanera and La Infanta deposits occur approximately 6km from each other. Near-term focus for the Emerita exploration team is to continue to expand the mineralization at La Romanera and explore the area between the two deposits with particular focus on the historic
Metallurgical sampling program, La Romanera and La Infanta commencing.
Resource Estimation Details and Methodology
Mineral Resource estimation was completed by
La Romanera and La Infanta are classified as volcanic-hosted massive sulphide (VHMS') deposits and occur as tabular strata-bound lenses of polymetallic (Zn, Pb, Cu, Ag, Au) massive sulphides. Drilling has so far defined five sulphide lenses used as estimation domains in Resource modelling: The Upper and
Drillhole samples were flagged by domain, composited to regular lengths and top-cuts applied to isolated outlier values. Variography was conducted on the composite data for each variable within each estimation domain.
Grades were estimated into block models sub-celled to the estimation domain boundaries. Grade and density estimation were conducted using ordinary kriging (OK) for most domains. Inverse Distance Squared (IDW2) was carried out in the La Infanta South 1 domain, where the number of composites was insufficient for effective variogram modelling. Hard boundaries were applied to constrain the interpolation. The estimates were run in a three-pass plan, using progressively larger search neighbourhoods. Distance based top-cuts were applied in higher estimation passes to limit grade extrapolation.
Estimated grades were validated globally, locally, and visually prior to classification. No material issues with the grade interpolation were identified. Classification has been limited to contiguous regions where nominal drill spacing is 50m or less for Indicated Resources and 100m or less for Inferred Resources.
Mining, processing and long-term price assumptions were used to evaluate the proportion of the block models that could reasonably be expected to be economically mined. A 3.0% ZnEq cut-off was selected in line with extraction via conventional underground mining methods. Thinner zones of mineralisation are present at La Infanta and reporting was further restricted to exclude blocks below 3.0% ZnEq when diluted over a 3m minimum mining width. The ZnEq calculation includes metallurgical recovery assumptions for each metal. Initial metallurgical test work is commencing and WAI has used recoveries within the range of other Iberian Pyrite Belt deposits and informed by review of petrographic studies. WAI cautions that changes in metallurgical recovery and/or payability assumptions could significantly impact the MRE.
IBW Geology and Mineralization
The 20km 2 Iberian Belt West (IBW) property is located in the south of
The geology of the IBW claim block comprises a mixed sequence of extrusive and intrusive volcanic rocks, volcaniclastic and marine sedimentary rocks that were folded and thrusted during the Variscan orogeny. The massive sulphide lenses at Romanera and Infanta are localized within the volcaniclastics and sediments, near to the contact with massive, felsic volcanics. The mineralized horizon is structurally repeated along the 10km length of IBW, defining several prospective corridors that are the focus of current exploration within the project areas.
At La Romanera, two steeply dipping massive sulphide lenses ranging between 2.0m and 32.0m in thickness strike west-northwest over at least 700m as currently defined. Stratigraphy is tightly folded, overturned to the south, and plunges gently to the west. Deep drilling is in progress to define the lower limits of these lenses, following down-dip extensions and indications from down-hole geophyics.
At Infanta, over a kilometer of shallow ancient workings along the contact between felsic volcaniclastics and tuffaceous shales define the mineralized horizon. These workings were confined to the hangingwall of a thrust fault, within 20m of surface, whereas the reported resource is to the footwall of the thrust and extends as two lenses to a depth of at least 350m below surface.
Romanera Mineralization
The 2023 Resource Estimate includes two lenses, showing a style of mineralization typical of VHMS deposits:
Upper Lens. Massive to semi-massive sulphide mineralization.
No stockwork-style mineralization is recognized in the deposit.
The Upper Lens massive sulphide is a continuous mineralized horizon which varies approximately from 2.0 to 32.0m in true thickness and averages 10.0m overall, with a strike length of 700m approximately.
The Lower Lens massive sulphide is a continuous mineralized horizon which varies approximately from 2.0 to 30.0m in true thickness and averages 13.0m overall, with a strike length of 720m.
The Upper Lens massive sulphide and the underlying
The Upper Lens occurs approximately 2.0 to 30.0 m in the hanging wall above the Lower Lens.
Infanta Mineralization
The 2023 Resource Estimate includes three blocks, showing a style of mineralization mainly typical of VHMS deposits:
North Block. Disseminated to massive sulphide mineralization.
South Block. Underlies the North Block and consists of disseminated to massive sulphide mineralization.
South Block 1. Underlies the South Block and consists of disseminated to massive sulphide mineralization.
No stockwork-style mineralization is recognized in the deposit.
The North Block massive sulphide is a continuous mineralized horizon which varies approximately from 1.0 to 10.0m in true thickness and averages 3.0 m overall, with a strike length of 1900m.
The South Block massive sulphide is a continuous mineralized horizon which varies approximately from 1.0 to 9.0 m in true thickness and averages 3.0 m overall, with a strike length of 1090 m approximately.
The South Block1 massive sulphide is a continuous mineralized horizon which varies approximately from 1.0 m to 7.0 m in true thickness and averages 2.6m overall, with a strike length of 325 m approximately.
The North Block massive sulphide and the underlying South Block are generally separated throughout the Deposit by about 30.0 m.
The South Block massive sulphide and the underlying South Block 1 are generally separated throughout the Deposit by about 15.0m. The Deposit dips at approximately 70 degrees from surface for a down-dip length of approximately 425 m (North Block), 190m (South Block) and 150m (South Block 1).
The South Block sits approximately 15.0m in the hanging wall above the South Block 1 in a structurally controlled system. The North Block sits approximately 30.0m in the hanging wall above the South Block in a structural controlled system.
About
Emerita is a natural resource company engaged in the acquisition, exploration and development of mineral properties in
Contact:
Tel: +1 647 910-2500
Email: info@emeritaresources.com
Cautionary Note Regarding Forward-looking Information
This press release contains 'forward-looking information' within the meaning of applicable Canadian securities legislation. Forward-looking information includes, without limitation, the mineralization of the
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