Dr. Harlan Meade reports
COPPER NORTH EXPANDS OXIDE MINERAL RESOURCE AT CARMACKS
Copper North Mining Corp. has expanded the oxide copper-gold-silver mineral resources at the Carmacks project, Yukon Territory. The mineral resource expansion is in the southern extension of the Carmacks mineral deposit, in zones 2000S, 13 and 12, on the basis of the step-out and infill drilling program conducted in September, 2017, and October, 2017, and the recently completed updated mineral resource estimate. The updated mineral resource has been prepared in accordance with National Instrument 43-101 -- Standards of Disclosure for Mineral Projects by independent qualified person, Dr. Gilles Arseneau, PGeo.
Highlights of the updated mineral resource in zones 2000S, 13 and 12:
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Step-out and infill drilling in fall 2017 was successful in confirming continuity of the mineral zones and grades of the oxide and sulphide mineralization in the southern extension of the Carmacks mineral deposit;
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Updated oxide measured and indicated mineral resource increased to approximately 4.3 million tonnes -- grading 0.47 per cent copper, 0.13 gram per tonne gold and 1.92 g/t silver:
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The new oxide measured and indicated mineral resource increased 40 per cent over the 2016 mineral resource, primarily from lateral expansion of the oxide mineralized zone -- upgrading of the already minor inferred resource category was a small contributor;
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The new oxide measured and indicated mineral resource in zones 2000S, 13 and 12 has the potential to provide an additional 2.4 years of mill feed at the planned processing rate of 1,775,000 tonnes per year, subject to economic confirmation by future mine development planning;
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The updated sulphide measured and indicated mineral resource totalled 4,416,000 tonnes grading 0.62 per cent copper, 0.13 g/t gold and 2.3 g/t silver, and an equal tonnage of mineral resource in inferred category.
Dr. Harlan Meade, president and chief executive officer, commented, "The increase of measured and indicated oxide mineralization in the updated mineral resource for the Carmacks project confirms there is an opportunity to undertake mine development engineering work on the southern extension to evaluate the potential for extending oxide mineralization mine life and for a potential future shift to mining the sulphide mineralization."
Updated oxide mineral resource
Zones 2000S, 13 and 12 are located 400 metres to 2,000 metres to the south of the proposed open pit, defined in the 2016 preliminary economic assessment based on the mineral resources in zones 1, 4 and 7. The oxide mineral resources occur from surface and extend to depths of 80 m to 100 m that may be amenable to open-pit mining with a modest strip ratio. The measured category represents 79 per cent of the total measured and indicated resource. The 2017 drill results, including location maps, are available in news releases dated Jan. 8 and Jan. 18 or on the Copper North website.
CARMACKS PROJECT UPDATED OXIDE MINERAL RESOURCE IN THE SOUTHERN EXTENSION ZONES -- APRIL 3, 2018
BASED ON A 0.15-PER-CENT ACID SOLUBLE CU CUT-OFF GRADE
Zone Tonnes (000) Total Cu (%) Acid soluble Cu (%) Sulphide Cu (%) Au (g/t) Ag (g/t)
Oxide -- measured
2000S 596 0.55 0.41 0.14 0.19 2.7
13 North 0 0 0 0 0 0
13 2,255 0.43 0.33 0.10 0.11 1.5
12 558 0.51 0.31 0.20 0.09 2.3
Total measured 3,409 0.46 0.34 0.12 0.12 1.8
Oxide -- indicated
2000S 303 0.55 0.38 0.17 0.17 2.6
13 North 0 0 0 0 0 0
13 227 0.35 0.25 0.09 0.12 1.19
12 365 0.54 0.41 0.14 0.09 2.50
Total indicated 895 0.50 0.36 0.14 0.12 2.20
Oxide -- measured and indicated
Total measured and indicated 4,304 0.47 0.34 0.13 0.12 1.92
Oxide -- inferred
2000S 23 0.56 0.37 0.18 0.17 2.80
13 North 247 0.31 0.26 0.05 0.13 1.40
13 80 0.28 0.22 0.06 0.09 1.20
12 39 0.57 0.41 0.16 0.10 3.50
Total inferred 389 0.34 0.27 0.07 0.12 1.65
Updated sulphide mineral resource
The updated sulphide measured and indicated mineral resource in zones, 2000S, 13 and 12 is 4,416,000 tonnes, of which 26 per cent is measured resource and 74 per cent is indicated resource. The measured resource is 1,136,000 tonnes, grading 0.59 per cent copper, 0.13 g/t gold and 2.3 g/t silver. The indicated resource is 3,280 tonnes, grading 0.63 per cent copper, 0.13 g/t gold and 2.3 g/t silver. The inferred mineral resource is 4,281,000 tonnes, grading 0.54 per cent copper, 0.12 g/t gold and 1.9 g/t silver. Additional drilling is warranted to confirm the grade, extent and continuity of the sulphide mineralization, and explore the potential for sulphide resource expansion.
UPDATED CARMACKS PROJECT SULPHIDE MINERAL RESOURCE IN THE SOUTHERN EXTENSION ZONES -- APRIL 3, 2018
BASED ON A 0.25-PER-CENT TOTAL CU CUT-OFF GRADE IN ZONES 2000S, 13 AND 12, AND ON A 0.15-PER-CENT
ACID SOLUBLE CU CUT-OFF GRADE IN THE ZONE 13 TRANSITION
Zone Tonnes (000) Total Cu (%) Acid soluble Cu (%) Sulphide Cu (%) Au (g/t) Ag (g/t)
Sulphide -- measured
2000S 292 0.65 0.08 0.57 0.15 3.1
13 596 0.57 0.11 0.47 0.13 1.8
13 transition 94 0.47 0.23 0.24 0.12 1.6
12 154 0.61 0.06 0.55 0.10 2.9
Total measured 1,136 0.59 0.11 0.49 0.13 2.3
Sulphide -- indicated
2000S 448 0.73 0.06 0.67 0.18 3.4
13 2,207 0.60 0.07 0.53 0.13 1.9
13 transition 54 0.55 0.29 0.26 0.15 1.8
12 571 0.69 0.06 0.64 0.11 3.1
Total indicated 3,280 0.63 0.07 0.56 0.13 2.3
Sulphide -- measured and indicated
Total measured and indicated 4,416 0.62 0.08 0.54 0.13 2.3
Sulphide -- inferred
2000S 636 0.73 0.05 0.68 0.18 3.5
13 3,474 0.51 0.05 0.46 0.11 1.6
13 Transition 17 0.72 0.26 0.46 0.18 2.6
12 154 0.44 0.04 0.40 0.07 1.4
Total inferred
Exploration opportunity
The success of exploration in the southern extension of the Carmacks deposit confirms that further exploration of both oxide and sulphide mineralization is warranted. Of particular interest is exploration of sulphide mineralization, both in the southern extension and in zones 1, 4 and 7.
Nov. 25, 2016, PEA mineral resource
The updated mineral resources are not included in the seven-year mine life estimated within the current preliminary economic assessment that considers open-pit mining 11.55 million tonnes of the oxide resources of zones 1, 4 and 7, grading 0.98 per cent Cu, 0.44 g/t Au and 4.34 g/t Ag (see NI 43-101 preliminary economic assessment "Technical report on the Carmacks project, Yukon, Canada," filed on SEDAR with a report date of Nov. 25, 2016).
Resource estimation methods
The updated mineral resource for zones 2000S, 13 and 12 is based on drilling conducted in 2006 and 2007 by Western Copper Corp. and additional drilling in 2014, 2015 and 2017 by Copper North. Copper minerals in the oxide resource largely consist of the acid-soluble minerals malachite, azurite and tenorite. The sulphide resources are located at depth and consist of chalcopyrite-bornite mineralization. In zone 13, a transition resource has been estimated, where chalcocite-native copper mineralization developed between the sulphide and oxide zones. The oxide, transition and sulphide zones were assessed visually during core logging and validated by the ratio of acid-soluble to total copper assays. Sulphide zones largely consist of material with less than 20 per cent of total copper as acid-soluble.
Wireframes for the mineralized zone were built in 3-D from the geological interpretation along and between cross-sections made up of fences of drill holes. Inverse distance to the second power was used to estimate grade in zones 12 and 2000S. Ordinary kriging was used to estimate grade in zone 13. The influence of anomalously high copper and silver assays was restricted by the capping of high values. The estimates were run in two passes: firstly, at 50 m by 50 m by 20 m, then at 100 m by 100 m by 45 m. A minimum of two drill holes with a minimum of three composites and a maximum of 12 composites were used to estimate resources. Blocks were classified as measured resources if they were estimated with four drill holes during pass one. Blocks that were estimated with two or three drill holes during pass one were classified as indicated resources; all other blocks were classified as inferred resources. A cut-off grade of 0.25 per cent total copper was used for the sulphide mineral resources. A cut-off grade of 0.15 per cent acid-soluble Cu was used to estimate oxide and transition mineral resources. Bulk density was estimated by inverse distance squared using a minimum of three density values from the geological unit, any blocks that had insufficient density data were assigned average density values determined by averaging all readings taken from the geological unit.
The previous mineral resources for zones 2000S, 13 and 12 were estimated in 2016. The updated mineral resource includes the 2007 resource, in addition to a revised estimate on zones 2000S, 13 and 12. Further details of the 2007 resource and the 2016 resource can be found in the NI 43-101 technical report for the Carmacks property, filed on SEDAR, with a report date of Nov. 25, 2016.
Quality assurance/quality control
A combination of HTW and NTW sized core were drilled by diamond drilling. Quality assurance and quality control procedures include the systematic insertion of duplicate and standard samples into the sample stream. Drill core samples were sawn in half, labelled, placed in sealed bags and were shipped straight to the preparatory laboratory of ALS Minerals in Whitehorse. All geochemical analyses were performed by ALS Minerals in North Vancouver. Total copper assays were performed by four-acid digestion with an AAS finish. Soluble copper assays were carried out by sulphuric acid digestion with an AAS finish. Gold was analyzed by a 30-gram charge fire assay with an AAS finish. Silver was analyzed by four-acid digestion and ICP-AES finish.
Qualified person
The 2007 resource for zones 1, 4 and 7 was prepared by an independent qualified person, Dr. Gilles Arseneau, PGeo, while employed at Wardrop (now Arseneau Consulting Services), and the 2016 resource for zones 2000S, 13 and 12 was prepared by an independent qualified person, Dr. Arseneau, PGeo, while employed at Arseneau Consulting Services. The 2007 resource and the 2016 resource are disclosed in the NI 43-101 preliminary economic assessment technical report on the Carmacks project, Yukon, Canada, with a report date of Nov. 25, 2016. The updated mineral resource estimate for zones 2000S, 13 and 12 was prepared in 2018 by an independent qualified person, Dr. Arseneau, PGeo, and will not be supported by an NI 43-101 technical report as the company does not consider the magnitude of change in total project mineral resources to be material. The estimates of mineral resources conform to the Canadian Institute of Metallurgy (CIM) Mineral Resource and Mineral Reserve definitions (May, 2014) referred to in National Instrument NI 43-101 -- Standards of Disclosure for Mineral Projects.
The technical information in this news release has been prepared, reviewed and approved by Dr. Meade, PGeo, the president and chief executive officer of Copper North, a qualified person within the meaning of NI 43-101.
About Copper North Mining Corp.
Copper North is a Canadian mineral exploration and development company. Its assets include the Carmacks project located in the Yukon, the Redstone property located in the Northwest Territories and the Thor property in British Columbia.
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