Espiritu trench at Bramaderos Au-Cu Project (Ecuador) exposes gold-silver polymetallic veins intersecting 4m at 415g/t silver, 0.9g/t gold, 6.9% zinc and 6.0% lead

OTTAWA, July 13, 2020 (GLOBE NEWSWIRE) — Cornerstone Capital Resources Inc. (“Cornerstone” or “the Company”) (TSXV-CGP) (F-GWN) (B-GWN) (OTC-CTNXF) is pleased to provide an update on its Bramaderos gold and copper joint venture in southern Ecuador in which it has a 12.5% interest carried by JV partner and project operator Sunstone Metals Inc. (ASX: STM) through to the start of commercial production (see “About Bramaderos”, below).

Figures related to this news release can be seen in PDF format by accessing the version of this release on the Company’s website (www.cornerstoneresources.com) or by clicking on the link below:

http://www.cornerstoneresources.com/i/pdf/NR20-16Figures.pdf.

HIGHLIGHTS:

  • Exploration at the Bramaderos gold-copper project in Ecuador has resumed with a staged re-entry consistent with covid-19 protocols
     
  • The initial focus is on the Espiritu gold-silver target where the first trench has been completed and intersected gold-silver polymetallic veins intersecting 4m at 415g/t silver, 0.9g/t gold, 6.9% zinc and 6.0% lead
     
  • This follows previously reported rock chip and float sampling that returned results of 4.2g/t gold and 101g/t silver, 11.9g/t gold and 175 g/t silver, and 11.6g/t gold and 2,962g/t silver
     
  • The Espiritu target, defined on the basis of gold and silver soil anomalies with supporting rock chip samples extends over an area of 800m x 600m with what appears to be multiple parallel mineralized structures
     
  • The trenching program is ongoing at Espiritu in preparation for a resumption of drilling in September
     
  • 12 other gold-silver targets are also being followed up including target E1, with more detailed soil sampling, including target E1 which has historical rock chip sampling returned results of up to 32.5g/t gold, 271g/t silver and 0.16% lead 1
     
  • Drill targeting and follow-up surface exploration over 5 porphyry targets is progressing well, and drilling at the Brama and Porotillo porphyry gold-copper targets is expected to begin in September

FURTHER INFORMATION:

The initial work program is focused on the Espiritu gold-silver target (Figures 1 & 2). The results from the first trench sampling program have been received and are shown in the table below. The system is interpreted to be a gold-silver polymetallic vein system (see below for technical explanation). Multiple targets within the broader Espiritu anomaly have been identified for further soil sampling, trenching and drilling.

Trench ES-01 Interval (m) Gold (g/t) Silver (g/t) Lead (%) Zinc (%)
  21 0.3 82.4 1.2 1.4
including 4 0.9 414.8 6.0 6.9
including 1 1.4 1001.0 16.9 5.7
           

Targeting of similar mineralized systems within the Bramaderos concession has been on-going during the Covid-19 shut down period and has resulted in the generation of multiple targets (Figure 1). These will be explored initially with more detailed soil sampling. This work has commenced at target E-1 (Figure 1).

Polymetallic Gold-Silver deposits:

Polymetallic gold-silver deposits are a class of epithermal to mesothermal vein deposits and replacement bodies which typically occur around the margins of porphyry gold-copper deposits. They are structurally controlled, display a range of gold-silver-lead-zinc-copper ratios and can occur over many kilometres around large porphyry systems. They appear to be relatively more common in South America and can develop into significant orebodies in their own right, such as Fresnillo in Mexico (83mt at 0.58g/t gold and 395g/t silver)(ref – J. Cunliffe, in Terry Leach Symposium 2008).

About Bramaderos

Measuring 4,948 hectares, the Bramaderos project is located approximately 130km from the Loja provincial capital in southern Ecuador. The project is easily accessible via the Pan American Highway that crosses the property.

The Bramaderos concession is owned by La Plata Minerales S.A. (“PLAMIN”), which in turn is owned 87.5% by Sunstone (the project operator) and 12.5% by Cornerstone. Cornerstone’s 12.5% interest is carried by Sunstone through to the start of commercial production and repayable at Libor plus 2% out of 90% of Cornerstone’s share of earnings or dividends from the Bramaderos project (see news release 20-01 dated January 7, 2020).

More information about the property can be found at www.cornerstoneresources.com.

Qualified Person:

Yvan Crepeau, MBA, P.Geo., Cornerstone’s Vice President, Exploration and a qualified person in accordance with National Instrument 43-101, is responsible for supervising the exploration program at the Bramaderos project for Cornerstone and has reviewed and approved the information contained in this news release.

Sampling and assaying

PLAMIN uses a fire assay gold technique for Au assays (FAS-111) and a four acid multi element technique (IMS-230) for a suite of 48 elements. FAS-111 involves Au by Fire Assay on a 30-gram aliquot, fusion and atomic absorption spectroscopy (AAS) at trace levels. IMS-20 is considered a near total 4 acid technique using a 20g aliquot followed by multi-element analysis by ICP-AES/MS at ultra-trace levels. This analysis technique is considered suitable for this style of mineralization.

Standards, blanks and duplicates are inserted ~1/28 samples. The values of the standards range from low to high grade and are considered appropriate to monitor performance of values near cut-off and near the mean grade of the deposit. The check sampling results are monitored and performance issues are communicated to the laboratory if necessary.

Sample security was managed through sealed individual samples and sealed bags of multiple samples for secure delivery to the laboratory by permanent staff of the joint venture. MS Analytical is an internationally accredited laboratory that has all its internal procedures heavily scrutinized in order to maintain their accreditation. MS Analytical is accredited to ISO/IEC 17025 2005 Accredited Methods.

PLAMIN’s sampling techniques and data have been audited multiple times by independent mining consultants during various project assessments. These audits have concluded that the sampling techniques and data management are to industry standards. All historical data has been validated to the best degree possible and migrated into a database.

Rock samples are collected by PLAMIN’s personnel, placed in plastic bags, labeled and sealed, and stored in a secure place until delivery by PLAMIN employees to the LAC y Asociados ISO 9001-2008 certified sample preparation facility in Cuenca, Ecuador.

Rock samples are prepared crushing to 70% passing 2 mm (10 mesh), splitting 250 g and pulverizing to 85% passing 75 microns (200 mesh) (MSA code PRP-910). Prepared samples are then shipped to MS Analytical Services (MSA), an ISO 9001-2008 laboratory in Langley, BC, Canada, where samples are assayed for a multi-element suite (MSA code IMS-136, 15.0 g split, Aqua Regia digestion, ICP-AES/MS finish) and gold by Fire Assay (MSA code FAS-111, 30 g fusion, AAS finish). Over limit results for Cu (>1%) are systematically re-assayed (MSA code ICF-6Cu, 0.2 g, 4-acid digestion, ICP-AES finish). Gold is assayed using a 30 g split, Fire Assay (FA) and AAS finish (MSA code FAS 111).  Over limit results for Au (>10 g/t) are systematically re-assayed (MSA code FAS-415, FA, 30g., gravimetric finish).

Soil samples are dried at low temperature, screened to 80 mesh (MSA code PRP-757); a 15 grams portion is then assayed for a multi-elements suite (MSA code IMS-136, Aqua Regia digestion, ICP-AES/MS finish).

Quality assurance / Quality control (QA/QC)

The MSA Analytical Laboratory is a qualified assayer that performs and makes available internal assaying controls. Duplicates, certified blanks and standards are systematically used (1 control sample every 20-25 samples) as part of PLAMIN’s QA/QC program. Rejects, a 100 g pulp for each rock sample, are stored for future use and controls.

About Cornerstone

Cornerstone Capital Resources Inc. is a mineral exploration company with a diversified portfolio of projects in Ecuador and Chile, including the Cascabel gold-enriched copper porphyry joint venture in northwest Ecuador. Cornerstone has a 21.4% direct and indirect interest in Cascabel comprised of (i) a direct 15% interest in the project financed through to completion of a feasibility study and repayable at Libor plus 2% out of 90% of its share of the earnings or dividends from an operation at Cascabel, plus (ii) an indirect interest comprised of 7.6% of the shares of joint venture partner and project operator SolGold Plc. Exploraciones Novomining S.A. (“ENSA”), an Ecuadoran company owned by SolGold and Cornerstone, holds 100% of the Cascabel concession. Subject to the satisfaction of certain conditions, including SolGold’s fully funding the project through to feasibility, SolGold Plc will own 85% of the equity of ENSA and Cornerstone will own the remaining 15% of ENSA.

Further information is available on Cornerstone’s website: www.cornerstoneresources.com and on Twitter. For investor, corporate or media inquiries, please contact:

Investor Relations:
Mario Drolet; Email: [email protected]; Tel. (514) 904-1333

Due to anti-spam laws, many shareholders and others who were previously signed up to receive email updates and who are no longer receiving them may need to re-subscribe at http://www.cornerstoneresources.com/s/InformationRequest.asp

Cautionary Notice:
This news release may contain ‘Forward-Looking Statements’ that involve risks and uncertainties, such as statements of Cornerstone’s beliefs, plans, objectives, strategies, intentions and expectations.  The words “potential,” “anticipate,” “forecast,” “believe,” “estimate,” “intend”, “trends”, “indicate”, “expect,” “may,” “should,” “could”, “project,” “plan,” or the negative or other variations of these words and similar expressions are intended to be among the statements that identify ‘Forward-Looking Statements.’  Although Cornerstone believes that its expectations reflected in these ‘Forward-Looking Statements’ are reasonable, such statements may involve unknown risks, uncertainties and other factors disclosed in our regulatory filings, viewed on the SEDAR website at www.sedar.com.  For us, uncertainties arise from the behaviour of financial and metals markets, predicting natural geological phenomena and from numerous other matters of national, regional, and global scale, including those of an environmental, climatic, natural, political, economic, business, competitive, or regulatory nature.  These uncertainties may cause our actual future results to be materially different than those expressed in our Forward-Looking Statements.  Although Cornerstone believes the facts and information contained in this news release to be as correct and current as possible, Cornerstone does not warrant or make any representation as to the accuracy, validity or completeness of any facts or information contained herein and these statements should not be relied upon as representing its views after the date of this news release.   While Cornerstone anticipates that subsequent events may cause its views to change, it expressly disclaims any obligation to update the Forward-Looking Statements contained herein except where outcomes have varied materially from the original statements.

On Behalf of the Board,
Brooke Macdonald
President and CEO

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

1 13 samples collected historically, along a ~N-S trench with 1m individual sample length, range gold 32.5 to 0.2g/t, average 2.7g/t. Range of Silver is 0.2 to 271.5g/t, and average 29.9g/t silver. Range of lead 7 – 1981ppm, with average 533ppm (0.05%). Note that grab samples are selected samples and are not necessarily representative of the mineralization hosted on the property. 

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