HIGHLIGHTS
- 36 variability composites from the Phase 4B and 4C test programs were selected from large-diameter (”PQ”) drill core from
Discovery Zone ,F Zone , Tallman,M Zone , andC/D Zone , representing a range of sample types across lithology and gold (“Au”) grade. - Key results include:
- 84.2% weighted average gold extraction1 from column leach tests for the 31 oxide composites.
- Gold extractions ranged from 52.7% to 94.2% for the oxide composites.
- >80% of leachable gold extracted within 10 days.
- Metallurgical testwork results on 149 composites and six bulk samples over five years are highly consistent, showing rapid leach kinetics, predictable grade-recovery and size-recovery relationships.
- Phase 5 composite selection and sample preparation is under way on an additional 25 variability composites from previously untested areas.
BLACK PINE METALLURGICAL TEST WORK
- Bulk sample column tests
- Phase 1A2 (6 x 300 kilogram surface bulk samples):
- 78.9% weighted average gold extraction, ranging up to 92.8%
- Phase 1A2 (6 x 300 kilogram surface bulk samples):
- Variability composite column tests (149 composites from PQ drill core)
- Phase 1B3 (29 composites):
- 82.9% weighted average gold extraction, ranging up to 94.5%
- Phase 24 (45 composites):
- 80.8% weighted average gold extraction, ranging up to 94.8%
- Phase 3 (15 low-grade composites):
- 65.2% weighted average gold extraction ranging up to 80.8% (see press release dated
October 27, 2021 )
- 65.2% weighted average gold extraction ranging up to 80.8% (see press release dated
- Phase 4A (24 composites):
- 86.9% weighted average gold extraction, ranging up to 95.8% (see press release dated
March 22, 2023 )
- 86.9% weighted average gold extraction, ranging up to 95.8% (see press release dated
- Phase 4B and 4C (36 composites):
- 84.2% weighted average gold extraction, ranging up to 94.2%.
- Phase 1B3 (29 composites):
Phase 4B and 4C composites and the pending Phase 5 variability test program filled gaps in the Black Pine resource metallurgical database. The Phase 4B and 4C data have updated the metallurgical recovery equations supporting the deposit-wide gold recovery model. Phase 5 initial results are expected in Q2 2024 and will support the on-going pre-feasibility engineering and economic study at Black Pine.
Phase 4B Test Results
Phase 4B focused on gap filling in
Phase 4B column tests produced the following results:
- Oxide material produced a weighted average 86.1% gold extraction, with a range from 56.9% to 94.2% gold extraction.
Phase 4C Test Results
Phase 4C focused exclusively on the
Phase 4C column tests produced the following results:
- A weighted average 73.4% gold extraction, with a range from 52.7% to 89.8% gold extraction.
For a graph of results of the Liberty Gold Phase 4B and 4C oxide variability composite results compared to previous test work, see Figure 1 below.
Figure 1: Black Pine Oxide Column Test Results – All Phases
*Data from columns of lower gold solubility are not shown in the above graph
For a table of laboratory test results of the Phase 4B and 4C variability composites click here:
http://ml.globenewswire.com/Resource/Download/0560ade5-e852-4a75-8457-532a5f860657
Gold extraction was rapid, with >80% of the leachable gold extracted within the first 10 days of column leaching for both phases of testing.
Five composites of lower gold solubility oxide materials were also tested and are not included in these results and are highlighted in orange in the table.
For graphs of results of the Phase 4B and 4C variability composite leach curves click here:
http://ml.globenewswire.com/Resource/Download/012ee6fd-9fff-437c-9be5-d7c8c7eda0a5
Laboratory Test Program
Samples for Phase 4B and 4C test work were obtained through drilling PQ core holes. Composites were selected through consideration of rock type, alteration, and gold grade to achieve a wide range of geo-metallurgical types. Composites were assembled in
For a map showing locations of all Black Pine bulk samples and core drill holes used for metallurgical testing, including Phase 4B and 4C, plus the upcoming Phase 5 test work see Figure 2, below.
Figure 2: Map of all Black Pine Bulk Sample and Metallurgical Core Locations
Program details included:
- Direct Leach (“DL”) and Carbon-in-Leach (“CIL”) coarse bottle roll tests (target of 80% passing 10 mesh or 1.7 millimeter (“mm”) particle size)
- DL and CIL fine bottle roll tests (target of 80% passing 200 mesh or 75 micron particle size)
- The DL samples were rolled/agitated in bottles in a 1.0 grams per liter (“g/l”) dilute sodium cyanide (“NaCN”) solution for 72 hours (for 200 mesh) or 144 hours (for 10 mesh).
- The CIL samples were rolled/agitated in bottles for 72 hours in a 1.0 g/l dilute NaCN solution, containing 20 g/l of activated carbon.
- Column composites were leached in 10.2 mm and 15.2 mm (four and six inch) diameter columns between 93 and 107 days. And were leached with low strength (0,50 g/l) NaCN solution. Gold and silver were recovered from column leach pregnant solutions by passing it through a small (separate) column containing activated carbon.
BLACK PINE METALLURGICAL DRILL CORE – PHASE 5
Results for the final four core holes from the 2023 PQ drill program are summarized in Table 1 below:
Table 1: Core Drilling Results from the 2023 PQ Drill Program*
Hole ID (Az, Dip) (degrees) | From (m) | To (m) | Intercept (m) | Au (g/t) | Au Cut-Off | Hole Length (m) | Target |
LBP973C (280, -70) | 7.3 | 14.5 | 7.2 | 0.69 | 0.15 | 44.9 | Rangefront |
LBP979C (310, -75) | 56.0 | 80.2 | 24.2 | 0.66 | 0.15 | 110.5 | |
and | 88.2 | 109.2 | 21.0 | 0.76 | |||
incl | 96.0 | 100.8 | 4.8 | 1.62 | 1.00 | ||
LBP980C (10, -46) | 78.1 | 84.7 | 6.6 | 0.86 | 0.15 | 47.9 | |
and | 89.9 | 92.4 | 2.4 | 0.30 | |||
and | 99.3 | 100.4 | 1.1 | 2.37 | |||
and | 136.9 | 142.1 | 5.2 | 0.82 | |||
LBP991C (80, -65) | 50.6 | 56.2 | 5.6 | 0.57 | 0.15 | 190.2 | Rangefront |
and | 78.6 | 109.1 | 30.5 | 0.22 | |||
and | 113.6 | 146.6 | 33.0 | 0.37 | |||
and | 163.3 | 173.1 | 9.8 | 1.41 | |||
incl | 165.8 | 173.1 | 7.3 | 1.80 | 1.00 | ||
and | 174.4 | 180.1 | 5.6 | 0.35 | 0.15 |
* Results are reported as drilled thicknesses, with true thicknesses approximately 50% to 90% of drilled thickness. Gold grades are uncapped. Au (g/t) = grams per tonne of gold; m=meters.
All metallurgical work at Black Pine has been supervised by Gary Simmons MMSA, formerly the Director of Metallurgy and Technology for Newmont Mining Corp.
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ABOUT
For more information, visit libertygold.ca or contact:
Phone: 604-632-4677 or Toll Free 1-877-632-4677
info@libertygold.ca
QUALITY ASSURANCE – QUALITY CONTROL
Drill composites were calculated using a cut-off of 0.10 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 50% to 90% of true width. Drill samples were assayed by ALS Limited in
All statements in this press release, other than statements of historical fact, are "forward-looking information" with respect to
Such forward-looking information, involves known and unknown risks, which may cause the actual results to be materially different from any future results expressed or implied by such forward-looking information, including, risks related to the interpretation of results and/or the reliance on technical information provided by third parties as related to the Company’s mineral property interests; changes in project parameters as plans continue to be refined; current economic conditions; future prices of commodities; possible variations in grade or recovery rates; the costs and timing of the development of new deposits; failure of equipment or processes to operate as anticipated; the failure of contracted parties to perform; the timing and success of exploration activities generally; the timing of the publication of any updated resources; delays in permitting; possible claims against the Company; labour disputes and other risks of the mining industry; delays in obtaining governmental approvals, financing or in the completion of exploration well as those factors discussed in the Annual Information Form of the Company dated
Although
Cautionary Note for
The information in this news release, including any information incorporated by reference, and disclosure documents of
Without limiting the foregoing, these documents use the terms “measured resources”, “indicated resources”, “inferred resources” and “probable mineral reserves”. Shareholders in
1 Weighted average gold extraction is obtained using the following equation: (composite head grade (grams/tonnes) multiplied by extraction (%) for all head grades)/sum of all head grades for composites defined as “Oxide” mineralization having a cyanide gold solubility greater than 65%. Using arithmetic averages tends to over-represent low grade composites and under-represent high grade composites. The arithmetic extraction average of the 36 column tests is 74.1%.
2 Previously referred to as “Phase 1” – see press release dated
3 Previously referred to as “Phase 2” – see press release dated
4 Previously referred to as “Phase 3” – see press release dated
Photos accompanying this announcement are available at
https://www.globenewswire.com/NewsRoom/AttachmentNg/14c6973f-e9bf-4382-b1de-f7fd7af198dc
https://www.globenewswire.com/NewsRoom/AttachmentNg/19f9ee6e-9004-4700-8a45-9fe3a5ee4098
Figure 1
Black Pine Oxide Column Test Results – All Phases
Figure 2
Map of all Black Pine Bulk Sample and Metallurgical Core Locations
2024 GlobeNewswire, Inc., source