Rokmaster Resources Corp. Develops Sediment Hosted Copper-Silver Targets at Big Copper
John Mirko, President and CEO of Rokmaster stated:
"For many years, Big Copper had been a secondary asset within Rokmaster's project portfolio. Our re-examination of the Big Copper Property has been predicated by:
- Rapid and substantial increases in copper and silver prices and projected supply short falls for these metals, and
- Greatly enhanced competitor activity in the search for sediment hosted copper deposits in southeastern British Columbia.
Big Copper has always been a significant sediment hosted copper-silver occurrence and the results of our prospecting surveys further support this conclusion. Exploration at Big Copper will be low cost and may offer high returns. Rokmaster looks forward to developing and implementing an exploration strategy to cost effectively advance Big Copper over the coming months."
Big Copper Property: The Big Copper Property tracks a mineralized deformation and alteration front for approximately 4.5 km defined by at least three adits, outcrops, seven trenches and several drillholes which support strong copper-silver mineralization (Figure 1). Mineralized zones are hosted within the 1,300 - 2,300 m thick Creston formation which is composed of fine-grained siltstones, argillites and dirty quartzites. Mineralization is best developed within a strong, 50 - 60 m wide deformation zone, forming along the western limb of a regional scale antiform. Mineralization is proximal from the transition from bright green, chlorite rich sediments to thin bedded yellow-cream quartz rich sediments. This color change may represent the change from reduced to oxidized fluids, a common signature of mineralization at sediment hosted copper deposits. At Big Copper, quartzite rock units may become increasingly calcareous representing a transitional contact with the overlying Kitchener Formation. The Creston formation is correlative with the Revett Formation which hosts several large copper-silver deposits and undeveloped occurrences in northern Montana and Idaho, including the Spar Lake, Montanore and Rock Creek deposits (Figure 2). Like the large sediment hosted copper deposits in the Revett formation, the Big Copper Property is unusual in that it hosts both copper and silver at significant levels.
Figure 1: Geology and Sample Location Map
Figure 2. Creston - Revett Stratigraphic Column
Mineralization at the Big Copper Property has two dominant styles including:
- Disseminated chalcopyrite-pyrite grains forming parallel to the dominant foliation and locally forming discrete sulphide bands.
- Clotted chalcopyrite grains hosted within bedding parallel, deformed quartz-siderite veins.
Copper-silver grades and widths in historical trenches and drillholes included1:
Trench 1: 5.5 m of 0.83% Cu and 23.3 g/t Ag.
Trench 3: 1.1 m of 1.20% Cu and 16.5 g/t Ag.
Trench 7: 2.0 m of 2.95 % Cu and 35.7 g/t Ag.
In 1965, Cominco collared 5 diamond drill holes at an elevation of approximately 1,830 m on the north side of the Saint Mary's River1. Four out of the five drillholes cored significant copper mineralization; significantly silver was not assayed for.
DDH 1A: 4.4 m of 3.30% Cu (within 29.7 m of 1.40% Cu).
DDH 3: 4.1 m of 1.20% Cu.
DDH 4: 3.0 m of 0.20% Cu.
DDH 5. 1.5 m of 1.60 Cu.
In 1967, four percussion drillholes targeted the Big Copper mineralized zone at an elevation of 1,370 m, also on the north side of the Saint Mary's River, cut:
Drillhole S1: 12.2 m of 0.92% Cu and 6.2 g/t Ag.
Drillhole S2: 9.1 m of 0.57% Cu and 3.4 g/t Ag.
Drillhole S3: 9.1 m of 0.19% Cu and trace Ag.
Drillhole S4: 9.1 m of 0.85% Cu and 12.0 g/t Ag.
Footnote (1). The condition of trenches and drillholes did not permit Rokmaster personnel to resample these historical mineralized intervals and the historical data is not 43-101 compliant. In addition, the reported widths of mineralization in trenches is likely to be representative of true widths but insufficient data exists to permit the calculation of true widths of the reported mineralized intervals in drillholes. The trench results, 1965 and 1967 drillholes, and their results, are cited in: Holcapek, F. 1976: Geological and Geophysical Report on the Bracebridge Property, Fort Steele Mining Division. BC Assessment Report No. 6206, 27 pages.
Rokmaster's prospecting team examined historical trenches, rock outcrops and waste dumps along the strike of the mineralized zone at Big Copper, Table 1. All samples were collected north of the Saint Mary's River over a strike length of approximately 1,000 m. The zone is also known to continue to the south of the Saint Mary's River, e.g. the 4600 Creek Showing, adding at least 2,500 m to the strike length of the known mineralized zone.
Over this broad area, seven rock and chip samples averaged 0.16 g/t Au, 77 g/t Ag and 3.43% Cu (Table 1.) Lead and zinc values within these samples are negligible. The copper-silver ratios are strong and within the range of historical averages. Significantly, the gold content ranges from 0.02 to 0.35 g/t Au and averages 0.17 g/t Au.
Table 1. Prospecting Sample Results - Big Copper.
Sample | Easting | Northing | Sample Type | Au g/t | Ag g/t | Cu % | Pb % | Zn % |
P304022 | 534874 | 5513494 | grab-rock | 0.35 | 147 | 12.559 | 0.01 | 0.08 |
P304019 | 534566 | 5512633 | 1.3 m chip | 0.19 | 128 | 2.927 | 0.005 | 0.05 |
P304017 | 534837 | 5513508 | grab-rock | 0.26 | 121 | 2.867 | 0.005 | 0.05 |
P310220 | 534886 | 5513536 | grab-rock | 0.13 | 72 | 2.659 | 0.02 | 0.04 |
P304020 | 534548 | 5512530 | grab-rock | 0.08 | 31 | 1.81 | 0.005 | 0.01 |
P304018 | 534837 | 5513508 | 1.1 m chip | 0.14 | 34 | 0.876 | 0.005 | 0.02 |
P304021 | 534848 | 5513556 | grab-rock | 0.02 | 7 | 0.317 | 0.005 | 0.01 |
The prospecting samples characterize the higher-grade mineralization. These results are within the range of those reported by previous operators, confirming that Big Copper is a robust copper-silver sediment hosted occurrence, and one which may have a significant structural overprint.
Quality Assurance/Quality Control. All prospecting rock samples were shipped to MSA Labs in Langley, British Columbia. MSA Labs is an ISO 17025 (Testing and Calibration Laboratory) and an ISO 9001 (Quality Management System) Certified Laboratory. Rock samples were crushed to 2 mm and a 500-gram sub sample was pulverized with 85% of the sample passing 75 microns. The sub sample was analysed using a combination of MSA Labs FAS211 for Au and ICP-240 (4 acid digestion) for silver, base metals and other trace elements. FAS211 for gold is an ore grade fire assay of a 50 g pulp with an AAS finish with a detection range between 0.01 and 100 ppm). ICP-240 utilizes four acid digestion and provides ore grade analytical data on silver, base metals and 26 other elements. In addition to internal MSA lab standards, Rokmaster submitted known standards into the sample stream.
The technical information in this news release has been prepared in accordance with Canadian regulatory requirements and reviewed and approved by Mr. Eric Titley, P. Geo., a Qualified Person as per National Instrument 43-101, who is independent of Rokmaster.
For shareholder information please contact: Mike Kordysz, mkordysz@rokmaster.com, Ph. +1 (604) 319-3171
On Behalf of the Board of Directors of
John Mirko
President & Chief Executive Officer.
Neither TSX Venture Exchange nor its Regulation Services Provider (as that term in defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this press release.
About Rokmaster
Rokmaster controls a portfolio of three significant exploration and development projects all of which are located in southern British Columbia in regions of excellent infrastructure. The three projects include:
- Revel Ridge. Rokmaster is currently conducting an underground drill program at the Revel Ridge project located in southeastern British Columbia 35 km's north of the City of Revelstoke. Revel Ridge hosts a high-grade gold and polymetallic orogenic sulphide deposit which has been the subject of a PEA Technical Report dated December 8, 2020.
- Big Copper. Rokmaster controls the Big Copper property in the Kimberley area of southern British Columbia. Big Copper is a high-grade copper-silver occurrence hosted in mid-Proterozoic rocks. Copper-silver mineralization has been traced for 4.5 km along strike and is exposed in a series of outcrops, adits and trenches over approximately 500 m of vertical relief. Big Copper likely belongs to a class of stratabound replacement copper-silver deposits hosted within mid - Proterozoic quartzitic sediments. The style and stratigraphic setting of mineralization at Big Copper may be analogous to similar stratabound silver-copper deposits in NW Montana, e.g. the Troy Mine (a significant past producer of copper and silver) or Hecla's Montanore pre-development project, with a reported inferred resource of 112 million tonnes at 54.8 g/t Ag and 0.7% Cu. (Hecla Mining Company 2020 Annual Report, pg. 119. www.hecla-mining.com).2
Footnote (2). The qualified person has been unable to verify this inferred resource.
- Duncan Lake Zinc. Duncan is a carbonate hosted silver-lead-zinc deposit located near Duncan Lake in southern British Columbia. The deposit is hosted within a Cambrian age Badshot Limestone which also hosts Ag-Pb-Zn mineralization at Teck Resources Limited recently producing Pend D'Oreille mine as well as past producers including the Blue Bell Mine, Reeves MacDonald Mine, Jersey-Emerald and HB Mines. Mineralization at Duncan Lake forms in the crest and limbs of the regional scale Duncan Lake anticline, where strong lead-zinc +/- silver mineralization has been traced by surface and underground drilling for approximately 2,500 m. At Duncan Lake, Rokmaster will be targeting >30 Mt of >10% Pb+Zn+Ag. Historical background and a geological synthesis of the Duncan Lake deposit is provided in a NI 43-101 report by Lane, B., 2018: Technical Report on the Duncan Lake Project.
CAUTIONARY NOTE REGARDING FORWARD LOOKING STATEMENTS: This news release may contain forward-looking information within the meaning of applicable securities laws ("forward-looking statements"). Forward-looking statements are statements that are not historical facts and are generally, but not always, identified by the words "expects," "plans," "anticipates," "believes," "intends," "estimates," 'projects," "potential" and similar expressions, or that events or conditions "will," "would," "may," "could" or "should" occur. These forward-looking statements are subject to a variety of risks and uncertainties which could cause actual events or results to differ materially from those reflected in the forward-looking statements, including, without limitation: risks related to fluctuations in metal prices; uncertainties related to raising sufficient financing to fund the planned work in a timely manner and on acceptable terms; changes in planned work resulting from weather, logistical, technical or other factors; the possibility that results of work will not fulfill expectations and realize the perceived potential of the Company's properties; risk of accidents, equipment breakdowns and labour disputes or other unanticipated difficulties or interruptions; the possibility of cost overruns or unanticipated expenses in the work program; the risk of environmental contamination or damage resulting from Rokmaster's operations and other risks and uncertainties. Any forward-looking statement speaks only as of the date it is made and, except as may be required by applicable securities laws, the Company disclaims any intent or obligation to update any forward-looking statement, whether as a result of new information, future events or results or otherwise.
SOURCE Rokmaster Resources Corp.
Contact
Mr. John Mirko, President & CEO of Rokmaster Resources Corp., jmirko@rokmaster.com, Ph. 1-604-290-4647 or the Company's website: www.rokmaster.com