VANCOUVER, British Columbia, Aug. 09, 2022 (GLOBE NEWSWIRE) — Liberty Gold Corp. (TSX: LGD; OTCQX: LGDTF) (“Liberty Gold” or the “Company”) is pleased to announce the results from a recently-completed sonic drilling program at the Goldstrike Oxide Gold Project in southwestern Utah (“Goldstrike”). The purpose of the program was to obtain material for metallurgical testing from the historic heap leach pads (“HHLP”), to determine how much gold remains and to what extent it can be recovered in a new heap leach mining operation. The program followed a 2018 reverse circulation (“RC”) drilling program, which indicated that considerable gold remains in the HHLP and in underlying backfill material.
Liberty Gold completed 815 metres (“m”) of sonic drilling in 23 holes in the two leach pads making up the HHLP and in adjacent and underlying backfill areas. All holes returned at least 15 m true thickness of above reporting cut-off grade (0.15 grams per tonne gold “g/t Au”) oxide gold mineralization, with some holes in the thicker portions of the pads returning up to 44 m of continuous mineralization. Cyanide solubility of gold in assay pulps, as expected, returned a wide range of values, but generally showed a good correlation between grade and solubility, with some higher-grade intervals returning in excess of 90% cyanide solubility. These data suggest that much of the gold in the HHLP was incompletely leached during the historic mining operation and is potentially available for extraction by re-leaching.
Material from the sonic drilling program will be shipped to Kappes Cassiday Associates in Reno, Nevada for metallurgical column testing under the guidance of the Company’s metallurgical consultant, Gary Simmons. Data from this program and the RC drilling will be used to estimate the gold available for leaching within the HHLP in support of further engineering studies.
Jon Gilligan, COO of Liberty Gold stated, “We are extremely pleased with the results of the sonic drilling program. With approximately 7.5 million tonnes of previously-leached material contained in these two pads, much of it still contains gold, it is likely that a significant portion could be re-treated in a modern heap leach operation. This study could enhance the economics of any future operation considerably, particularly in the crucial first year or two of operation. We look forward to the results of the metallurgical testing so we can take the next steps in optimising the economic viability of the Goldstrike deposit.”
For a map and cross sections of the sonic drilling, including drill collars and traces for the current release, please click here:
https://libertygold.ca/images/news/2022/August/Goldstrike_NR08092022MapSection.pdf
For a complete table of drill results from current Liberty Gold drill holes at Goldstrike, please click here: https://libertygold.ca/images/news/2022/August/GS_Intercepts08092022.pdf
SONIC DRILLING HIGHLIGHT TABLE*
| Hole ID (Az, Dip) (degrees) | From (m) | To (m) | Intercept (m) | Au (g/t) | Au Cut-Off | Hole Length (m) | Target | Comments | g/t x m | AuCN/ AuFA% |
| PGS873 (0, -90) | 1.5 | 38.1 | 36.6 | 0.63 | 0.15 | 46.5 | Leachpad 2 | Leachpad | 30.8 | 56% |
| including | 9.1 | 38.1 | 29.0 | 0.75 | 0.20 | 57% | ||||
| and including | 35.1 | 38.1 | 3.0 | 2.97 | 1.00 | 68% | ||||
| and | 38.1 | 45.7 | 7.6 | 1.02 | 0.20 | Backfill | 46% | |||
| including | 38.1 | 42.7 | 4.6 | 1.51 | 1.00 | 45% | ||||
| PGS876 (0, -90) | 0.0 | 38.1 | 38.1 | 0.27 | 0.15 | 51.1 | Leachpad 2 | Leachpad | 12.9 | 54% |
| including | 4.6 | 38.1 | 33.5 | 0.28 | 0.20 | 55% | ||||
| and | 38.1 | 42.7 | 4.6 | 0.59 | 0.20 | Backfill | 41% | |||
| including | 41.1 | 42.7 | 1.5 | 1.00 | 1.00 | 50% | ||||
| PGS879 (0, -90) | 3.0 | 21.3 | 18.3 | 0.49 | 0.15 | 35.1 | Leachpad 2 | Leachpad | 12.6 | 60% |
| including | 4.6 | 21.3 | 16.8 | 0.52 | 0.20 | 62% | ||||
| and | 21.3 | 35.1 | 13.7 | 0.27 | Backfill | 62% | ||||
| PGS881 (0, -90) | 0.0 | 9.1 | 9.1 | 0.24 | 0.15 | 30.5 | Leachpad 2 | Leachpad | 7.6 | 71% |
| including | 0.0 | 7.6 | 7.6 | 0.25 | 0.20 | 72% | ||||
| and | 15.2 | 22.9 | 7.6 | 0.71 | 0.15 | 52% | ||||
| including | 16.8 | 22.9 | 6.1 | 0.85 | 0.20 | 52% | ||||
| and including | 19.8 | 21.3 | 1.5 | 1.59 | 1.00 | 45% | ||||
| PGS884 (0, -90) | 0.0 | 19.8 | 19.8 | 0.31 | 0.20 | 50.3 | Leachpad 2 | Leachpad | 17.1 | 51% |
| and | 19.8 | 42.7 | 22.9 | 0.48 | 0.15 | Backfill | 63% | |||
| including | 19.8 | 33.5 | 13.7 | 0.67 | 0.20 | 61% | ||||
| and including | 30.5 | 33.5 | 3.0 | 1.46 | 1.00 | 59% | ||||
| PGS887 (0, -90) | 0.0 | 15.2 | 15.2 | 0.57 | 0.15 | 25.9 | Leachpad 2 | Leachpad | 11.8 | 83% |
| including | 0.0 | 13.7 | 13.7 | 0.61 | 0.20 | 84% | ||||
| and including | 0.0 | 3.0 | 3.0 | 1.16 | 1.00 | 84% | ||||
| and including | 6.1 | 7.6 | 1.5 | 1.03 | 94% | |||||
| including | 15.2 | 22.9 | 7.6 | 0.40 | 0.20 | Backfill | 88% | |||
| PGS888 (0, -90) | 0.0 | 13.7 | 13.7 | 0.60 | 0.20 | 28.2 | Leachpad 2 | Leachpad | 11.0 | 71% |
| including | 12.2 | 13.7 | 1.5 | 1.09 | 1.00 | 90% | ||||
| and | 13.7 | 16.8 | 3.0 | 0.35 | 0.20 | Backfill | 80% | |||
| and | 18.3 | 28.2 | 9.9 | 0.18 | 0.15 | 61% | ||||
| PGS890 (0, -90) | 0.0 | 18.3 | 18.3 | 0.43 | 0.15 | 35.1 | Leachpad 1 | Leachpad | 9.6 | 44% |
| including | 4.6 | 18.3 | 13.7 | 0.52 | 0.20 | 45% | ||||
| and | 27.4 | 33.5 | 6.1 | 0.27 | 0.15 | Backfill | 65% | |||
| PGS891 (0, -90) | 0.0 | 25.9 | 25.9 | 1.02 | 0.15 | 35.8 | Leachpad 1 | Leachpad | 26.3 | 80% |
| including | 0.0 | 18.3 | 18.3 | 1.37 | 0.20 | 82% | ||||
| and including | 4.6 | 13.7 | 9.1 | 2.17 | 1.00 | 86% | ||||
| and including | 15.2 | 16.8 | 1.5 | 1.15 | 82% | |||||
| PGS892 (0, -90) | 0.0 | 30.5 | 30.5 | 0.63 | 0.20 | 39.6 | Leachpad 1 | Leachpad | 19.3 | 79% |
| including | 4.6 | 7.6 | 3.0 | 1.75 | 1.00 | 93% | ||||
| including | 10.7 | 12.2 | 1.5 | 1.09 | 80% | |||||
| PGS894 (0, -90) | 0.0 | 24.4 | 24.4 | 0.54 | 0.15 | 29.7 | Leachpad 1 | Leachpad | 13.2 | 66% |
| including | 9.1 | 24.4 | 15.2 | 0.77 | 0.20 | 70% | ||||
| and including | 13.7 | 15.2 | 1.5 | 1.29 | 1.00 | 90% | ||||
| and including | 21.3 | 24.4 | 3.0 | 1.23 | 71% | |||||
| PGS895 (0, -90) | 1.5 | 19.8 | 18.3 | 0.77 | 0.15 | 29.0 | Leachpad 1 | Leachpad | 14.1 | 86% |
| including | 1.5 | 18.3 | 16.8 | 0.82 | 0.20 | 86% | ||||
| and including | 10.7 | 18.3 | 7.6 | 1.51 | 1.00 | 91% | ||||
| PGS897 (0, -90) | 1.5 | 19.8 | 18.3 | 0.37 | 0.20 | 25.9 | Leachpad 1 | Leachpad | 7.3 | 66% |
| including | 1.5 | 3.0 | 1.5 | 1.75 | 1.00 | 95% | ||||
| and | 19.8 | 21.3 | 1.5 | 0.23 | 0.15 | Backfill | 66% | |||
| PGS899 (0, -90) | 0.0 | 13.7 | 13.7 | 0.68 | 0.20 | 22.9 | Hassayampa Pit | Backfill | 9.4 | 60% |
| including | 0.0 | 4.6 | 4.6 | 1.14 | 1.00 | 69% | ||||
| PGS900 (0, -90) | 0.0 | 41.9 | 41.9 | 0.30 | 0.15 | 41.9 | Hamburg Pit | Backfill | 12.8 | 79% |
| including | 0.0 | 9.1 | 9.1 | 0.46 | 0.20 | 89% |
*Please refer to the full table at the link above for complete results. Results are reported as drilled thicknesses, with true thicknesses approximately 90% to 100% of drilled thickness. Gold grades are uncapped. Au (g/t) = grams per tonne of gold. “AuCN/AuFA” is the ratio of cyanide soluble gold (recovered using the method described in the Quality Assurance – Quality Control section below) to gold by fire assay, expressed as percent.
KEY POINTS:
- A Sonic drilling program consisting of 815 m in 23 holes was completed on and adjacent to the historic heap leach pads at Goldstrike. A sonic drill rig uses an ultrasonic vibration to drill without the use of drilling mud and is the “best practice” drilling technique to sample unconsolidated rock piles.
- Sonic drilling of the HHLP returned thick, above reporting cut-off intervals of gold mineralization in every drill hole.
- Much of the gold exhibits moderate to high cyanide solubility, with over 90% solubility in higher-grade intervals.
- The high grades and cyanide solubility suggest that portions of the HHLP contain gold that was not recovered during the original mining operation, and which may be available for recovery in a future operation.
- Results will be used to determine the gold content remaining in the HHLP, while composites of the drilled material will be used for metallurgical column testing to determine how much of the gold is recoverable by heap leaching.
- The backfill material directly underlying the leach pads also contains gold, including 22.9 m grading 0.48 g/t Au in PGS884. Backfill material adjacent to the HHLP is also mineralized, including 13.7 m grading 0.68 g/t Au in PGS899.
ABOUT GOLDSTRIKE
Goldstrike is located in the eastern Great Basin, immediately adjacent to the Utah/Nevada border, and is a Carlin-style gold system, similar in many ways to the prolific deposits located along Nevada’s Carlin trend. Like Black Pine and the Nevada Gold Mines Long Canyon deposit, Goldstrike represents part of a growing number of Carlin-style gold systems located off the main Carlin and Cortez trends in underexplored parts of the Great Basin.
Goldstrike is a past-producing, open-pit run of mine heap-leach operation that produced 209,000 ounces (“oz”) of gold and 197,000 oz of silver between 1988 and 1994 during a period of historically low gold prices. Ore was mined from 12 shallow pits, at an average grade of 1.2 g/t Au. Liberty Gold carried out extensive compilation, drilling and metallurgical work, releasing a resource estimate and Preliminary Economic Assessment (“PEA”) in 2018. The resource includes an Indicated 925,000 ounces (“oz”) of gold grading 0.50 g/t Au (57,846,000 tonnes) and an Inferred 296,000 oz of gold grading 0.47 g/t Au (19,603,000 tonnes), backed by over 1,700 drill holes. The PEA mines 915,516 oz of gold at a life of mine all in sustaining costs of US$793/oz, returning a NPV at a 5% discount rate (“NPV5%”) of US$129.5 million and an IRR of 29.4% at US$1,300/oz gold prices. A sensitivity analysis using US$1,700/oz gold returns an NPV5% of US$291.7 million and an Internal Rate of Return of 52.4% representing strong economic returns at current gold prices.
The 2022 drilling campaign is in progress including metallurgical and RC resource drilling. On completion of this program the RC drill will be moved to the Black Pine oxide gold deposit in Idaho to accelerate resource drilling and the testing of new regional gold targets.
A virtual site tour and 3D model of the Goldstrike property, including details about the geology and mineralization, is available on the Company’s website: libertygold.ca
QUALITY ASSURANCE – QUALITY CONTROL
Drill composites were calculated using cut-offs of 0.15 g/t Au, 0.20 g/t Au and 1.00 g/t Au. Drill intersections are reported as drilled thicknesses. True widths of the mineralized intervals vary between 30% and 100% of the reported lengths due to varying drill hole orientations but are typically in the range of 60% to 80% of true width. Drill samples were assayed by ALS Limited in Reno, Nevada for gold by Fire Assay of a 30 gram (1 assay ton) charge with an AA finish, or if over 5.0 g/t Au were re-assayed and completed…
Read More:Liberty Gold Reports Excellent Results from Sonic Drilling
2022-08-09 10:00:00
