The Aurizon Zone, located in the southeast corner of the Lac La Hache Property (yellow circle in image), is viewed by EnGold management as having the potential for high grade gold-copper-silver underground mining. EnGold has specifically targeted the Aurizon South area, which has yielded the best gold/copper/silver values within a strong structure demonstrating excellent continuity.
Drilling at Aurizon South indicates gold-copper-silver occurs within a near-vertical structure that measures at least 400m along strike (open), with true widths ranging from 2 m to more than 20 m and extending to 670 m depth with most recent drilling (open). High grades are associated with sulphide-rich (chalcopyrite, chalcocite, pyrite) hydrothermal breccia and related fractures. In fall, 2016, drilling intersected bonanza grades, exceeding 50 gpt Au and as high as 263 gpt Au, associated with quartz veins lying adjacent to the structure, featuring abundant visible gold specks and semi-massive sulphides. Quartz veins have been intersected in surface trenches, and drill holes down to more than 550 m vertical depth (open). Silicification also occurs within the main hydrothermal breccia structure, associated with improved grades (see recent assays in EnGold’s Oct. 26/16, Nov. 23/16, Dec. 21/16 and Jan 18/17 News).
Gold assays from historical and recent drilling include 10.36 grams per tonne (gpt) over 14m (downhole length), 6 gpt/8 m, 26.3 gpt/ 3 m, 6.7 gpt/6 m, 5.1 gpt/10 m, 5.7 gpt/4 m, 6.7gpt/6 m, 11.7 gpt/5 m, 10.7 gpt/2 m, 15.5 gpt/1.9 m, 15.7 gpt/1.8 m and many wider intervals of 3-4 gpt gold. Many of these intervals also carry 1-3 % copper, and 15-96 gpt silver.
Resource Estimate
On January 19th, 2018, EnGold reported that independent geologist Garth Kirkham, P.Geo., of Kirkham Geosystems Ltd (“KGL”) completed and provided to EnGold a maiden Mineral Resource Estimate on the Aurizon South Gold Zone. Due to increasing metals prices, the estimate in the 2018 report was revised upward in 2021 to an Inferred Mineral Resource of 1,991,000 tonnes at a grade of 3.18 g/t AuEq, 2.32 g/t Au, 0.60% Cu and 5.3 g/t Ag based on a 2.0 g/t Gold Equivalent cut-off grade. The 2018 Kirkham Technical report was also replaced by “43-101 Technical Report for EnGold Mines Ltd. (Lac La Hache Project) by SRK Consulting (Canada) Inc.
The estimate is based on the 65 drill holes that have intercepted the structure to date, which remains open for expansion on strike and down dip. The gold-bearing Aurizon South also has significant amounts of copper and silver, and as such, the Company is expressing the resource as a gold equivalent, which incorporates the value of the copper and silver into the resource.
Inferred Mineral Resource cut-off sensitivities at Aurizon
| Cut-off g/t |
Tonnes (000’s) | AuEq g/t |
Au g/t |
Cu % |
Ag g/t |
AuEq ounces (000’s) |
|---|---|---|---|---|---|---|
| 1 | 4,141 | 2.27 | 1.61 | 0.46 | 3.99 | 302 |
| 1.25 | 3,491 | 2.48 | 1.76 | 0.50 | 4.36 | 278 |
| 1.5 | 2,787 | 2.77 | 1.99 | 0.54 | 4.81 | 248 |
| 1.75 | 2,323 | 3.00 | 2.17 | 0.57 | 5.15 | 224 |
| 2 | 1,991 | 3.18 | 2.32 | 0.60 | 5.37 | 204 |
| 2.25 | 1,617 | 3.43 | 2.54 | 0.62 | 5.58 | 178 |
| 2.5 | 1,367 | 3.62 | 2.70 | 0.64 | 5.72 | 159 |
| 3 | 733 | 4.36 | 3.51 | 0.59 | 5.52 | 103 |
Source: Kirkham 2021
Notes:
- The current Mineral Resource Estimate was prepared by Garth Kirkham, P. Geo ., of Kirkham Geosystems Ltd.
- All mineral resources have been estimated in accordance with Canadian Institute of Mining and Metallurgy and Petroleum (“CIM”) definitions, as required under National Instrument 43-101 (“NI 43-101”)
- Mineral resources were constrained using mainly geological constraints and approximate AuEq grade domains.
- AuEq values were calculated using average long-term prices of $1,600/oz Au, $21/0z Ag, $3.00/lb Cu, and metal recoveries of 92% Au, 95% Cu, and 90% Ag were used. Base case cut-off grade assumed approximately $90/t operating and sustaining costs. All prices are stated in USD$.
- Mineral resources are not mineral reserves until they have demonstrated economic viability. Mineral resource estimates do not account for a resource’s mineability, selectivity, mining loss, or dilution. All figures are rounded to reflect the relative accuracy of the estimate, and, therefore, numbers may not appear to add precisely.
- An Inferred Mineral Resource has a lower level of confidence than that applying to an Indicated Mineral Resource and must not be converted to a Mineral Reserve. It is reasonably expected that the majority of Inferred Mineral Resources could be upgraded to Indicated Mineral Resoureces with continued exploration.