K92 Mining Inc. is pleased to announce results from the ongoing diamond drilling of the Kora deposit at the Kainantu gold mine in Papua New Guinea.
The results for the latest 35 diamond drill holes completed from underground into the Kora deposit are summarized in Table 1 below. The results continue to demonstrate the high-grade and continuity of Kora with intersections largely focused on increasing drill density up-dip, down-dip and to the south to upgrade resources for the Stage 3 Expansion Feasibility Study. In addition, some step-out drilling and testing of veins that are outside the resource, including the K2 Hanging Wall and the K3 veins, is also being undertaken.
From the drilling results, all drill holes intersected mineralization and 25 intersections exceeded 10 g/t AuEq with 45 intersections exceeding 5 g/t AuEq. Exploration has continued to observe an escalation of grade as drill density has progressively increased from a ~100 m x ~100 m spacing to a ~25 m x ~25 m spacing up-dip, down-dip and to the south. The drilling results are highlighted by hole KMDD0266 recording multiple intersections including 7.20 m at 59.00 g/t Au, 56 g/t Ag and 3.89% Cu (64.88 g/t AuEq, 4.69 m true width) and, ~25 m to the South, hole KMDD0270 intersecting 11.27 m at 15.46 g/t Au, 13 g/t Ag and 1.10% Cu (17.09 g/t AuEq, 6.67 m true width) both at the K1 Vein. These results expanded a known area of high-grade mineralization.
Results of increasing drill density up-dip and down-dip continue to show intersections of significant mineralization, highlighted by KMDD0280 recording multiple intersections including 6.82 m at 34.80 g/t Au, 22 g/t Ag and 1.59% Cu (37.19 g/t AuEq, 5.05 m true width) at the K2 Vein and 12.65 m at 12.86 g/t Au, 6 g/t Ag and 0.39% Cu (13.45 g/t AuEq, 8.19 m true width) at the K1 Vein. KMDD0299 also intersected 12.26 m at 19.38 g/t Au, 32 g/t Ag and 1.14% Cu (21.31 g/t AuEq, 8.06 m true width) at the K2 Vein.
Drilling to the south recorded numerous high-grade intersections. Highlights include: KMDD0283 recording 10.00 m at 5.53 g/t Au, 41 g/t Ag and 2.86% Cu (9.85 g/t AuEq, 8.62 m true width); KMDD0277 recording 8.70 m at 6.98 g/t Au, 74 g/t Ag and 3.78% Cu (12.94 g/t AuEq, 8.67 m true width), and; KMDD0291, located outside the mineral resource envelope, recording 9.60 m at 1.84 g/t Au, 38 g/t Ag and 5.20% Cu (9.25 g/t AuEq, 6.58 m true width).
Drilling also recorded multiple intersections along the underexplored K2 Hanging Wall and K3 veins, highlighted by KMDD0263 recording 7.84 m at 17.52 g/t Au, 23 g/t Ag and 2.44% Cu (21.04 g/t AuEq, 5.09 m true width) at the K2 Hanging Wall vein and KMDD0289 recording 3.05 m at 12.47 g/t Au, 28 g/t Ag and 1.63% Cu (14.98 g/t AuEq, 2.44 m true width) at the K3 vein. As the number of drill rigs significantly increased during 2020, there is now more capacity to test these veins, which are beyond the western extent of the K2 vein. The K2 Hanging Wall and K3 veins were not part of the April 2020 NI 43-101 resource estimate.
Long sections of K1 and K2 showing the location of the latest drill holes are provided in figures 1 and 2, respectively. A long section showing Kora drilling to date is provided in figure 3. A core photograph of drill hole KMDD0266 is provided in figure 4.
John Lewins, K92 Chief Executive Officer and Director, stated, “The recent drilling results from Kora continue to demonstrate the continuity and high-grade nature of the vein system, with all 35 holes intersecting mineralization, 25 intersections above 10 g/t AuEq and 45 intersections above 5 g/t AuEq. These intersections also recorded solid thickness, averaging 3.16 metres and 4.78 metres true thickness for the K1 and K2 veins, respectively. Most importantly, as demonstrated by the long-sections (see Figure 1 and 2), drilling density often increases average localized grade, and step-out drilling continues to intersect mineralization outside of the mineral resource.
We are also encouraged by the results from the underexplored K2 Hanging Wall vein and the K3 vein, with KMDD0263 recording 7.84 metres at 21.04 g/t AuEq at the K2 Hanging Wall vein and KMDD0289 recording 3.05 metres at 14.98 g/t AuEq at the K3 vein. Neither of these veins are included in any of our mineral resource estimates and to date our drill capacity has limited our ability to allocate drill metres beyond the K2 vein to the west. With the drill fleet expanding considerably, our ability to test these veins in addition to other vein systems and porphyries concurrently has significantly increased.”
Key Assumptions and Parameters – Kora Deposit
The Kora Deposit comprises two parallel, steeply west dipping, north-south striking quartz-sulphide vein systems, K1 and K2, within an encompassing dilatant structural zone hosted by phyllite. An additional structure, the Kora Link, has also been defined between K1 and K2. There are five Kora Link structures identified, of which three are included in the resource estimate.
The current resource estimate area covers an area of approximately 1,250 metres along strike by 1,050 to 1,150 metres vertically representing ~75% of the drill target area. K92 plans to continue to drill the area not yet drilled. The resource estimate includes results from 266 diamond drill holes in addition to face samples taken from horizontal development and from cut and fill faces along the K1 and K2 veins.
Underground drilling consists of diamond core for a range of core sizes depending on the length of hole and expected ground conditions. Sampling is sawn half core under geological control and generally ranges between 0.5 m to 1.0 m. Underground face sampling is completed for every fired round and is to industry standard. QA/QC data indicated no significant issues with the sampling or the accuracy of the on-site analysis. Current core recovery of the mineral zone is +95%, with initial drilling around the 90% mark.
Geological logging is consistent and is based on a full set of logging codes covering lithology, alteration, and mineralization.
The geological interpretation of the vein systems is represented as 3D wireframe solids snapped to a combination of diamond drillhole data and underground face sampling. Definition of the wireframes is based on identified gold mineralization in drill core nominally at a 0.1-0.2 g/t Au gold-off in conjunction with geological control/sense and current mining widths.
The wireframes were used to extract 1-metre composites (minimum of 0.5 m) from the drillhole and sampling database for gold, copper and silver. A gold top cut of 1,000 g/t was applied to K2 composites and a 150 g/t top cut for the Kora Link #2. No top cuts were applied to silver or copper. Variography was generally poor, as would likely be expected, although K1 indicated better along strike grade continuity.
Grade interpolation of the composite data was completed using Ordinary Kriging with a block size of 1 m x 5 m x 5 m. A larger block size check model indicated no evidence of over-smoothing of gold grade with the smaller block size.
Default average density values have been applied to the different lodes. The defaults are based on limited core measurements using the Archimedes Method (weight in air/weight in water). Density (t/m3) is on a per zone basis, with K1 and Kora Link: 2.84 t/m3; K2: 2.93 t/m3; Waste: 2.8 t/m3.
A three-pass search strategy was applied to the grade interpolation. Search ellipse parameters are listed below. Search ellipse orientations generally reflected the subtle changes in dip and strike of the vein systems, with up to 8 search domains used for each lode.
Drill Hole Sampling Methodology, QA/QC and Qualified Person
Diamond drill holes are first logged to determine the sampling intervals, which range from a minimum of 0.1 metres to generally 1 metre. The drill core is sawn half core cut along a reference line, with the remainder of the core returned to the core tray. Core samples are then placed in numbered calico and plastic bags, with a numbered sample ticket for dispatch to the assay laboratory. Samples are separately assayed for gold, copper and silver. K92’s procedure includes the insertion standards, blanks and duplicates. Gold assays are by the fire assay method. Copper and silver assays are by three-acid-digestion method (nitric, perchloric & hydrochloric mix).
K92 maintains an industry-standard analytical quality assurance and quality control (QA/QC) and data verification program to monitor laboratory performance and ensure high quality assays. Results from this program confirm reliability of the assay results. All sampling and analytical work for the mine exploration program is performed by Intertek Testing Services (PNG) LTD, an independent accredited laboratory that is located on site. External check assays for QA/QC purposes are performed at SGS Australia Pty Ltd in Townsville, Queensland, Australia.
The analytical QA/QC program is currently overseen by Andrew Kohler, PGeo, Mine Geology Manager and Mine Exploration Manager for K92. Andrew Kohler, a qualified person under the meaning of Canadian National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”), has reviewed and is responsible for the technical content of this news release.
K92 Mining Inc. is engaged in the production of gold, copper and silver from the Kora deposit at the Kainantu Gold Mine in the Eastern Highlands province of Papua New Guinea, as well as exploration and development of mineral deposits in the immediate vicinity of the mine. The Company declared commercial production from Kainantu in February 2018 and is in a strong financial position.
The Company commenced an expansion of the mine based on an updated Preliminary Economic Assessment on the property which was published in January 2019 and updated in July 2020. K92 is operated by a team of mining company professionals with extensive international mine-building and operational experience.
On Behalf of the Company,
John Lewins, Chief Executive Officer and Director
For further information, please contact David Medilek, P.Eng., CFA at +1-604-687-7130.