Effective
2023 Snip MRE Highlights:
Updated MRE of 823,000 ounces grading 9.35 g/t Au in the Indicated category and 114,000 ounces grading 7.10 g/t Au in the Inferred category
An increase of 579,000 Au ounces in the Indicated Resource, representing a growth of 237% since the 2020 MRE
2021 and 2022 drilling programs heightened confidence of historical drilling data and improved certainty in continuity of the ore body
Metallurgical recovery increased to 96% from 90%
Removal of 40 metre QAQC buffer
In the 2020 MRE, a 40 metre omnidirectional 3-D buffer was created around the Skeena holes drilled during 2016 to 2019 as these recent holes contained QAQC data, whereas the historical assays had no other preserved data to substantiate the results. The 2020 classification strategy forced all Indicated Resources that were qualified by adequate drill spacing outside of this 40 metre buffer to be downgraded to Inferred Resources.
During the 2021 and 2022 infill drilling programs, 28 twin drill holes totaling 3,318 metres were drilled to validate the historical drill intercepts. Comparative vein intervals and gold grades were captured in both the original and twin holes. Corresponding vein interval statistics demonstrated proper correlations between the historical fire assays and the twin hole fire assays. This has enabled the historical drill hole data to be used during the grade estimation process without additional constraints.
Specific Gravity
In the 2020 MRE, two density values were applied to the model; a value of 2.78 g/cm3 for vein mineralization, and 2.86 g/cm3 for the Biotite Spotted Unit ('BSU'). An additional 1,770 specific gravity measurements were incorporated into the 2023 model, which were reassessed within their appropriate lithology and vein units. The 2023 MRE utilized a value of 2.91 g/cm3 for vein mineralization, and 2.84 g/cm3 for the BSU.
Application of Dynamic Anisotropy
Veins were estimated in Skeena's 2020 MRE using the single-search ellipsoid of the variogram. In the 2023 update, dynamic anisotropy ('DA') was used for the larger veins showing good continuity, whereby the search ellipse was adjusted on a block-by-block basis using a surface that defines the overall folded orientation of the veins. DA allows the estimator to select composite intervals that are in the most suitable orientation, thereby resulting in an estimate that is locally more accurate and more in line with the original vein model interpretation.
Expected Economic Study
The Company expects to release a detailed engineering study with project economics on Snip in H1 2024. The study will highlight Snip as a potential satellite operation, providing feed to a centralized mill at Eskay Creek. Skeena expects the additional clean, high-grade mineralization from Snip to further bolster the mine life at Eskay Creek and likely reduce smelter penalties.
About Skeena
Contact:
Tel: +1 604 684 8725
The Independent and Qualified Person for the Snip MRE is Ms.
Snip 2023 MRE Notes
Mineral resources are not mineral reserves and do not have demonstrated economic viability. There is no certainty that all or any part of these Mineral Resources estimated will be converted into mineral reserves.
The effective date of the MRE is
The close out date of the Snip database was
In accordance with NI 43-101 recommendations, the number of metric tonnes was rounded to the nearest thousand. Any discrepancies in the totals are due to rounding effects.
Estimates use metric units (metres, tonnes and g/t). Metal contents are presented in troy ounces (metric tonne x grade / 31.10348)
Reasonable prospects for eventual economic extraction were determined by means of applying stope optimization parameters summarized in Table 3. Resources are reported in-situ and undiluted within the veins contained within potentially economical and minable underground long hole stope shapes.
The underground cut-off grade for the long hole mining method was calculated to be 2.5 g/t Au. Cut-off grades must be re-evaluated considering prevailing market conditions (including gold prices, exchange rates and costs).
Cut-off grades are based on a metal price of
Mineral Resources have been depleted to account for past production and exclude mineralization within a 1 m buffer around historical underground developments. This 1 m exclusion zone is low and will need to be expanded in future resource estimates.
An additional 307 drill holes for a total meterage of 46,268 m has been included into this estimate since the 2020 Maiden Mineral Resource.
Two block models (
Block tonnage was estimated from volumes using a density of 2.91 g/cm3 for all lithologies except the unmineralized BSU which used a density of 2.84 g/cm3.
Three mineralization domains were created to constrain the estimate: V, S and TW. The V and S domains are a collection of veins that occur in the
A total of 94 veins were modelled: 13 V-Veins, 71 S-Veins and 10 TW-Veins.
The vein model was created in Leapfrog GeoTM using composite intervals greater than or equal to 1.0 g/t Au if following interpreted structures and displaying mineralization continuity. Locally, lower grades were included in the veins if continuity was displayed. Local minor edits were done in
Assays were composited to 1.5 m honoring vein domain boundaries. To handle partial interval lengths, composites were distributed equally.
Grade capping was performed on vein coded composites. Gold capping ranged from 40 - 350 g/t in the V-Veins, 100 - 215 g/t in the S-Veins and 45 - 110 g/t in the TW-Veins.
Gold variograms were used to determine the spatial relationship of grade over distance.
Maximum continuity in the V-Veins, S-Veins, and TW-Veins was 50 m, 55 m, and 45 m, respectively.
Ordinary Kriging was used for the estimation of gold in all vein domains using the 1.5 m equally distributed composites and honouring hard vein boundaries. Composite lengths of less than 0.1 m were excluded from the estimate.
In the V- and -S veins that were continuous and greater than 237,000 tonnes, and TW-veins greater than 100,000 tonnes, a DA surface was utilized during estimation to honour locally varying vein orientations.
Mineral Resources were estimated using three passes having increased variogram range-based search radii. Pass 1, 2, and 3 used variogram ranges of 2/3 range, range, and 2 times the range respectively. A 4th Pass was used for global statistical reporting and was not used in Classification.
Indicated and Inferred Resources were classified according to the following scheme: The Indicated category is defined by blocks interpolated during Pass 1 and 2 only, using a minimum of 3 drill holes, and an average distance of less than 35 metres (approximately 70% of the average variogram range).
The Inferred category is defined by blocks interpolated during Pass 1, 2 and 3, using a minimum of 2 drill holes and an average distance less than 75 metres (approximately 50% more than the average variogram range)
Blocks were locally reclassified to reduce 'spotted' Indicated resources within Inferred resources and vice versa.
The quantity and grade of reported Inferred mineral resources in this estimation are uncertain in nature and there has been insufficient exploration to redefine the Inferred mineral resources as Indicated mineral resources. It is uncertain if further exploration will result in upgrading them to the indicated mineral resources category.
Cautionary note regarding forward-looking statements
Certain statements and information contained or incorporated by reference in this press release constitute 'forward-looking information' and 'forward-looking statements' within the meaning of applicable Canadian and
Readers should not place undue reliance on such forward-looking statements. Any forward-looking statement speaks only as of the date on which it is made and the Company does not undertake any obligations to update and/or revise any forward-looking statements except as required by applicable securities laws.
Cautionary note to U.S. Investors concerning estimates of mineral Reserves and mineral Resources
Skeena's mineral Reserves and mineral Resources included or incorporated by reference herein have been estimated in accordance with National Instrument 43-101 - Standards of Disclosure for Mineral Projects ('NI 43-101') as required by Canadian securities regulatory authorities, which differ from the requirements of
In addition, investors are cautioned not to assume that any part or all of Skeena's mineral Resources constitute or will be converted into Reserves. These terms have a great amount of uncertainty as to their economic and legal feasibility. Accordingly, investors are cautioned not to assume that any 'measured', 'indicated', or 'inferred' mineral Resources that Skeena reports are or will be economically or legally mineable. Further, 'inferred mineral Resources' have a great amount of uncertainty as to their existence, and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all or any part of an 'inferred mineral resource' will ever be upgraded to a higher category. Under Canadian securities laws, estimates of 'inferred mineral Resources' may not form the basis of feasibility or prefeasibility studies, except in rare cases where permitted under NI 43-101.
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