Coro Mining Marimaca Exploration Update: Atahualpa Underground Sampling Demonstrates 800 Metre Extension of Marimaca Mineralization
VANCOUVER, British Columbia, Nov. 27, 2018 (GLOBE NEWSWIRE) -- Coro Mining Corp. (“Coro” or the “Company”) (TSX: COP) is pleased to announce further exciting exploration results from its Marimaca project. Results from the sampling of historic underground workings in the Atahualpa area indicate a continuous 800 metre extension of mineralization to the north of the Marimaca 1-23 resource, announced in April 2018. A 17,000 metre RC drilling program has commenced at Atahualpa, increased from the original 12,000 metre plan to test for potentially thicker mineralization.
|Underground Sampling Highlights|
|•||Sampling of underground working returned positive results with an average grade for the total 2,098 samples of 0.72 % CuT and 0.56 % CuS.|
|38 metres at 0.8 % CuT and 0.68 % CuS|
|76 metres at 0.64 % CuT and 0.50 % CuS|
|186 metres at 1.57 % CuT and 1.31 % CuS|
|48 metres at 1.24 % TCu and 1.03 % CuS|
|258 metres at 0,95 % CuT and 0.75 % CuS|
|64 metres at 0.67 % CuT and 0,49 % CuS|
|84 metres at 1.10 % CuT and 0.76 % CuS|
|50 metres at 0.91 % CuT and 0.71 % CuS|
|90 metres at 0.78 % CuT and 0.56 % CuS|
|•||Brochantite rich copper oxide mineralization shown to extend 800 metres beyond limits of previous resource estimate at Marimaca 1-23, and to be open in all directions.|
Exploration activities at Atahualpa have been aided by historic and easily accessible sub-horizontal mine workings that extend for approximately 800 metres in a north-north west direction from the Marimaca 1-23 resource limits, and to a depth of 100 metres below surface. Consequently, a total of approximately 2,000 metres of continuous underground workings have been geologically mapped and channel sampled.
The results demonstrate that the rock types, structures and copper oxide mineralization are similar to those observed at Marimaca 1-23; consisting of parallel, 50° east dipping fractures in monzodiorite intruded by dacitic to dioritic dykes, hosting brochantite dominated mineralization. Figure 1 shows the location of the Atahualpa underground workings in relation to the previously reported drilling.
Underground workings are north-south, north-north west and east-west oriented, accessible by truck and display good rock quality conditions. Although no reports on earlier mining activities exist, it is believed from sampling and the continuous copper oxide mineralization exposed in the declines and adits that the workings were developed to mine material estimated to contain above 2% copper.
Figure 2 shows the distribution of copper in the workings and the location of selected intervals. This demonstrates consistent grades of 0.6 - 0.8% CuT and above, clearly indicating that mineralization continues significantly to the north from the Marimaca 1-23 resource.
The diagram in Figure 3 illustrates a long geological section containing the drilling already conducted at Marimaca and La Atómica. The red zone illustrates the planned drilling area at Atahualpa, following the excellent results from the underground sampling.
Figure 4: Atahualpa underground workings; selected intersections
|Underground Drive||Intersection||% CuT*||% CuS*|
|From (m)||To (m)||Length (m)|
|* % CuT: total copper|
|** % CuS: acid soluble copper|
Atahualpa RC Drilling Program
The Company has now commenced an RC drilling program at Atahualpa, the main objective of which is to define the continuation of copper mineralization northwards from the Marimaca 1-23 resource.
The program comprises a 100 x 100 metres grid covering an area of 400 x 750 metres. This area was previously mapped and sampled including the sampling of the underground workings whose results were reported here. Oxide copper mineralization was observed in many outcrops, access roads as around drill pad locations. It is believed that the nature and controls of mineralization are identical to those observed at Marimaca 1-23.
Originally 51 holes for a total 12,310 metres were planned, but because mineralization appears to be thicker than originally anticipated, the program has been increased to 17,000m to drill to greater depths.
Phase II Program Upcoming Milestones
The Marimaca Phase II exploration program is advancing according to plan. Following the announcement of preliminary drill results from La Atómica earlier this month, the Company is on track to complete and announce all drill results for La Atómica by the end of the year, in addition to results from the sampling of underground workings in that area. The Company also anticipates announcing the first batch of drill results from Atahualpa before the end of the year.
Sample and Assay Protocol
The samples were taken as 2 metres continuous chip channel samples in previously carefully cleaned surface walls. Both adit walls were sampled by Coro personnel. The samples were transported to the Andes Analytical Assays (“AAA”) preparation laboratory in Calama. Samples were prepared using the following standard protocol: drying, crushing to better than 80% passing -10#, homogenizing, splitting and pulverizing a 400 g subsample to 95% passing -150#. All samples were assayed for CuT and CuS by AAS. No standards, blanks or duplicates were employed. After sampling, underground workings were geologically mapped in detail following a protocol adapted from that used for bore hole logging, with emphasis on mineralization and its structural and litohologic controls.
The technical information in this news release, including the information that relates to geology, drilling and mineralization of the Marimaca Phase I and II exploration programs was prepared under the supervision of, or has been reviewed by Sergio Rivera, Vice President of Exploration, Coro Mining Corp, a geologist with more than 38 years of experience and a member of the Colegio de Geologos de Chile and of the Institute of Mining Engineers of Chile, and who is the Qualified Person for the purposes of NI 43-101 responsible for the design and execution of the drilling program and the contents of this news release.
|For further information please visit www.coromining.com or contact:|
|Nicholas Bias, VP Corporate Development & Investor Relations|
|Office:||+56 2 2431 7601|
|Cell:||+44 (0)7771 450 679|
Forward Looking Statements
This news release includes certain “forward-looking statements” under applicable Canadian securities legislation. These statements relate to future events or the Company’s future performance, business prospects or opportunities. Forward-looking statements include, but are not limited to, statements regarding the future development and exploration potential of the Marimaca Project. Actual future results may differ materially. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated in such statements. Forward-looking statements reflect the beliefs, opinions and projections on the date the statements are made and are based upon a number of assumptions and estimates that, while considered reasonable by Coro, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements and the parties have made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: the inherent risks involved in the mining, exploration and development of mineral properties, the uncertainties involved in interpreting drilling results and other geological data, fluctuating metal prices, the possibility of project delays or cost overruns or unanticipated excessive operating costs and expenses, uncertainties related to the necessity of financing, the availability of and costs of financing needed in the future as well as those factors disclosed in the Company’s documents filed from time to time with the securities regulators in the Provinces of British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland and Labrador. Accordingly, readers should not place undue reliance on forward-looking statements. Coro undertakes no obligation to update publicly or otherwise revise any forward-looking statements contained herein whether as a result of new information or future events or otherwise, except as may be required by law.