Highlighted by 126 metres at 1.54% CuT and 118 metres at 0.93% CuT
VANCOUVER, British Columbia, June 19, 2019 (GLOBE NEWSWIRE) -- Coro Mining Corp. (“Coro” or the “Company”) (COP.TO) is pleased to provide an update for the Marimaca Project in the Antofagasta Region of Chile.
Results have now been received from the final fifth batch of 17 RC holes for 4,300 metres at Atahualpa, identifying new multiple high grade zones as well as primary sulphide mineralisation at depth.
Results from the drilling confirmed oxide mineralization, including:
- Hole ATR-66, from 24 to 70 metres, 46metres averaging 1.25% CuT
- Hole ATR-78, from 54 to 86 metres, 32 metres averaging 0.68% CuT
- Hole ATR-80, from 54 to 104 metres, 50 metres averaging 0.57% CuT
- Hole ATR-85, from 26 to 84 metres, 58 metres averaging 0.77% CuT
- Hole ATR-87, from 140 to 166 metres, 26 metres averaging 1.10% CuT
- Hole ATR-94, from 18 to 38 metres, 20 metres averaging 0.74% CuT
Results from the drilling confirmed mixed oxide-enriched sulphide mineralization, including:
- Hole ATR-66, from 76 to 110 metres, 34 metres averaging 3.14% CuT
- Hole ATR-75, from 76 to 118 metres, 42 metres averaging 1.73% CuT
- Hole ATR-77, from 44 to 104 metres, 60 metres averaging 0.81% CuT
- Hole ATR-81, from 48 to 74 metres, 26 metres averaging 0.94% CuT
- Hole ATR-87, from 188 to 206 metres, 18 metres averaging 1.68% CuT
- Hole ATR-93, from 144 to 166 metres, 22 metres averaging 1.41% CuT
Results from the drilling confirmed primary sulphide mineralization, including:
- Hole ATR-78, from 178 to 204 metres, 26 metres averaging 0.97% CuT
- Hole ATR-79, from 122 to 138 metres, 16 metres averaging 1.4% CuT
- Hole ATR-82, from 206 to 250 metres, 44 metres averaging 1.05% CuT
- Hole ATR-84, from 148 to 174 metres, 26 metres averaging 0.84% CuT
- Hole ATR-85, from 84 to 120 metres, 36 metres averaging 1.68% CuT
- Hole ATR-93, from 180 to 218 metres, 38 metres averaging 1.04% CuT
- Hole ATR-94, from 78 to 126 metres, 78 metres averaging 1.30% CuT
Commenting on the results, Luis Tondo, President and CEO said: “We are very excited by these results at Atahualpa. We have discovered new multiple high grade zones within the oxide zone at surface, and for the first time, we are also starting to see fairly continuous higher grade primary sulphide and secondary mineralization open at depth.
These results continue to confirm our thesis that Marimaca has the potential to be a large-scale open pittable copper deposit and will now be incorporated in the enlarged project resource estimate, which remains on track for completion during the third quarter 2019.”
The final 17 RC holes for 4,300 metres brings the total number of reported RC holes at Atahualpa to 92 for a total 24,816 metres. The original drill program envisaged 51 holes for 12,310 metres being completed by the end of the first quarter 2019; the additional 41 holes and 12,506 have taken extra time and therefore completed during the second quarter. The fifth batch drill holes are illustrated in Figure 1 below.
Figure 1: Atahualpa 5th-batch RC holed locations
Phase II Drilling
The Marimaca Phase II program commenced in Q4 2018 and has been designed to determine the extension of the orebody across the Atómica, Atahualpa and Tarso areas, with a view to publishing an enlarged and combined mineral resource estimate for the whole Marimaca project in Q3 2019.
The Atahualpa RC drilling is now complete, and the drilling for the Marimaca Phase II will be completed shortly. A diamond drill program of 15 holes totalling 4,500 metres at La Atómica and Atahualpa is ongoing and will assist with metallurgical testing for a Preliminary Economic Assessment (PEA). In addition, the Company is also undertaking a smaller RC drilling campaign at Tarso, targeting 19 holes for 5,300 metres. The results from both are anticipated in Q3 2019. The remaining drill holes will complement the 100 X 100 metre exploration of the oxide mineral zone across the Phase II area, the more detailed drilling of the La Atómica southwest limit along the Manolo zone, the east-west program which will allow a better understanding of higher copper grade feeders controlling mineralization along Atahualpa and La Atómica areas, and the recent extra drill metres devoted to define the high grade zones.
Deposit Size and High-Grade Zones
It is now known that the oxide deposit extends 1.4 kilometre along a north-northwest strike direction and attains a maximum width of approximately 800 metres along an east-west direction and a thickness of 100 to 150 metres, containing at least four well defined higher grade zones, three of which are exposed from surface. The principal higher grade zone presently identified is estimated to measure approximately 250 x 250 metres and located in the central part of a 90 metre thick oxide blanket.
The latest drill results permit the interpretation of the existence of other higher-grade zones located at Atahualpa and La Atómica as they correspond to either feeders or parallel fracture controlled mantos, mostly at the intersection of both.
Newly Identified Primary Mineralisation at Atahualpa
The results show that the higher grade mineral zones result from the process of supergene alteration of a high grade primary preserved at depth and converted in turn to enriched sulphides and then oxide mineralization during supergene alteration. For the first time, drilling has intercepted more continuous primary mineralization which reveals a potential that was not previously considered. An interpretation of the several high-grade zones is illustrated in plan view in Figure 2, as a cross section in Figure 3, and a long section in Figure 4 below.
Figure 2: Phase II Map showing interpreted higher-grade zones with reference to Marimaca 1-23 block model location
Figure 3: Cross section
Figure 4: Long section
Sampling and Assay Protocol
True widths cannot be determined with the information available at this time. Coro RC holes were sampled on a 2-metre continuous basis, with dry samples riffle split on site and one quarter sent to the Andes Analytical Assay preparation laboratory in Calama and the pulps then sent to the same company laboratory in Santiago for assaying. A second quarter was stored on site for reference. Samples were prepared using the following standard protocol: drying; crushing to better than 85% passing -10#; homogenizing; splitting; pulverizing a 500-700g subsample to 95% passing -150#; and a 125g split of this sent for assaying. All samples were assayed for CuT (total copper), CuS (acid soluble copper), CuCN (cyanide soluble copper) by AAS and for acid consumption. A full QA/QC program, involving insertion of appropriate blanks, standards and duplicates was employed with acceptable results. Pulps and sample rejects are stored by Coro for future reference.
Figure 5: Atahualpa Intersections
|ATR-66||350||0||126||126||1.54||Oxide - Mixed - Enriched|
|76||110||34||3.14||Mixed - Oxide - Enriched|
|and||236||262||26||0.42||Enriched - Oxide|
|and||326||344||18||0.31||Enriched - Primary|
|and||76||118||42||1.73||Primary - Mixed - Oxide|
|including||76||92||16||3.46||Primary - Mixed - Oxide|
|104||118||14||1.20||Oxide - Mixed|
|ATR-77||200||44||122||78||0.68||Enriched - Primary|
|including||44||104||60||0.81||Enriched - Primary|
|ATR-78||300||50||108||58||0.67||Oxide – Enriched2|
|90||108||18||0.76||Oxide - Enriched|
|and||136||166||30||0.58||Oxide - Enriched - Primary|
|including||138||160||22||0.72||Oxide - Enriched - Primary|
|and||50||60||10||0.33||Oxide - Mixed|
Atahualpa intersections continued,
|and||224||234||10||0.31||Primary - Enriched|
|and||44||112||68||0.60||Oxide - Mixed - Enriched|
|including||48||74||26||0.94||Oxide - Mixed - Enriched|
|88||112||24||0.59||Oxide - Mixed - Enriched|
|and||124||184||60||0.44||Primary - Enriched|
|including||152||170||18||0.73||Primary - Mixed|
|182||194||12||0.82||Primary - Mixed - Enriched|
|ATR-82||250||58||100||42||0.31||Oxide - Enriched - Primary|
|and||206||250||44||1.05||Enriched - Primary|
|222||232||10||3.22||Enriched - Primary|
|ATR-83||200||2||102||100||0.43||Oxide - Mixed - Primary|
|including||44||72||28||0.84||Oxide - Mixed|
|and||126||174||48||0.57||Oxide - Mixed - Primary|
|including||126||144||18||0.27||Oxide - Mixed|
|148||174||26||0.84||Mixed - Primary|
|and||194||206||12||1.36||Enriched - Primary|
Atahualpa intersections continued,
|ATR-85||200||2||120||118||0.93||Oxide - Enriched - Primary|
|84||120||36||1.68||Enriched - Primary|
|ATR-87||300||88||120||32||0.32||Oxide - Mixed|
|and||138||214||76||0.80||Oxide - Enriched - Primary|
|188||206||18||1.68||Enriched - Primary|
|ATR-92||200||6||102||96||0.49||Oxide - Mixed|
|64||102||38||0.50||Oxide - Mixed|
|ATR-93||300||144||166||22||1.41||Oxide - Mixed - Enriched|
|and||180||242||62||0.79||Primary - Enriched|
|including||180||218||38||1.04||Primary - Enriched|
|and||64||136||72||0.98||Oxide - Primary|
|including||78||126||48||1.30||Primary - Oxide|
|150||160||10||0.60||Oxide - Mixed|
|and||146||168||22||0.33||Mixed - Primary|
1 ATR-70, from 40 to 42 metres includes 2 metres not recovered due to passing through an historic underground working
2 ART-78, from 86 to 90 metres includes 4 metres not recovered due to passing through an historic underground working
3 ATR-80, from 72 to 76 metres includes 4 metres not recovered due to passing through an historic underground working
Figure 6: Fifth Batch Atahualpa Drill Collars
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 program 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 36 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.
Coro Mining and the Marimaca Project
Marimaca is fast becoming recognised as one of the most significant copper discoveries in Chile in recent years as it represents a new type of discovery which challenges accepted exploration wisdom and promises to open up new frontiers for discoveries elsewhere in the country. Marimaca is an intrusive orebody while the mantos deposits in the region are volcanic, which saw it overlooked by the major copper producers in the past, although it behaves like a volcanic setting as the extensive fracturing provides space for mineralisation to enter.
With a lack of new copper exploration discoveries in Chile the growing Marimaca resource is likely to make it a sought-after development project as it is situated in the coastal belt at low elevation close to Antofagasta and Mejillones. This prime location could enable its future development at a relatively modest capital investment. Marimaca would benefit from nearby existing infrastructure including roads, powerlines, ports, a sulphuric acid plant, a skilled workforce and seawater.
For further information please visit www.coromining.com or contact:
Nicholas Bias, VP Corporate Development & Investor Relations
Cell: +44 (0)7771 450 679
Office: +56 2 2431 7601
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.