More strong assays expand Alba gold-copper discovery at the Bramaderos Project, Ecuador
OTTAWA, April 27, 2022 (GLOBE NEWSWIRE) — Cornerstone Capital Resources Inc. (« Cornerstone » or « the Company ») (TSXV:CGP; OTC:CTNXF; FWB:GWN1) is pleased to provide an update on its Bramaderos gold and copper joint venture in southern Ecuador (see Figures 1 and 2) in which it has a 12.5% interest carried by JV partner and project operator Sunstone Metals Ltd. (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:
- Drilling continues to return grades in line with, or better than, other porphyry gold-copper deposits demonstrating Alba is an outstanding gold-copper porphyry discovery with scale.
- Alba is interpreted to be a gold rich gold-copper porphyry deposit with significant vertical extent, and with an upper gold zone locally containing visible gold. It is one of a cluster of systems currently being tested with drilling at Bramaderos.
- Results contain significant, consistent gold-copper intervals greater than 300m, with high-grade sub-intervals.
- Results include:
- 345.5m at 0.37g/t gold and 0.13% copper from 82.5m in BMDD022 including:
- 24m at 0.70g/t gold and 0.18% copper from 306m
- 397m at 0.30g/t gold and 0.10% copper from 102m in BMDD025 including:
- 22m at 0.61g/t gold and 0.14% copper from 159m
- 345.5m at 0.37g/t gold and 0.13% copper from 82.5m in BMDD022 including:
- BMDD024 intersected a gold zone of 2.8m at 1.21g/t gold located 350m from the previously reported upper gold zone (7m at 27g/t) hence expanding this target area.
- All holes have intersected copper as chalcopyrite, bornite and covellite in variably veined stockwork porphyry. Local visible gold was identified in BMDD025.
Cornerstone VP Exploration, Yvan Crepeau, said:
« With each set of assay results the Alba gold-copper porphyry grows in scale. We are now seeing a consistently well mineralized system with local higher grades of significant scale.
« The mineralization extends from surface to greater than 400m deep, where the system is wide open and untested. The grades are in line with or better than those seen in many gold-copper porphyries around the world.
« Current drilling is testing both the lateral extent and the vertical extent based on the recent results from an electrical geophysical survey which suggest a 1,000m vertical extent.
« Drill hole BMDD024 also intersected a narrow but significant gold zone located 350m away from the centre of the Alba porphyry. This could support the concept of high-grade roots of epithermal veins also over-printing the upper porphyry body ».
* The reader is cautioned that there has been insufficient exploration to define a mineral resource at Bramaderos and it is uncertain if further exploration will result in the target being delineated as a mineral resource.
Results from hole BMDD022 now include the extension of the original hole that ended in mineralization (see news release dated March 7, 2022). The extension added an additional 106m down-hole of gold-copper mineralized rock. The hole was drilled at a low angle and therefore has significantly broadened the gold-copper porphyry deposit near surface (see Figure 4).
Drill hole BMDD024 was drilled southwest of the main target area during a period when electrical geophysics was being completed over the main target zone, precluding drilling in the target area. Significantly, BMDD024 intersected a narrow massive sulphide zone that also contained gold, suggesting potential for high-grade roots of epithermal veins also over-printing porphyry mineralization in the area.
BMDD025 was drilled below hole BMDD023 (which intersected 84.2m at 0.51g/t gold and 0.16% copper from 183m, within 222.4m at 0.37g/t gold and 0.13% copper from 76.4m).
BMDD025 has added nearly 200m of additional vertical extent to this well mineralized system below BMDD023 (Figure 5). Drill hole BMDD027 has further tested this vertical extent a further 100-250m below BMDD025 on this section (assays pending).
This additional drilling is adding to the scale of the system which now measures at least 300m in diameter and a vertical extent exceeding 400m (and potentially up to 1,000m based on geophysics (see news release dated March 17, 2022).
Project operator Sunstone currently has 3 rigs operating at Alba. Those rigs are drilling holes 28, 30 and 31 (Figures 3 & 4).
Assay results to date from Alba include:
Measuring 4,948 hectares, the Bramaderos project is ideally located immediately adjacent to the Pan American highway, and within reasonable distance of available hydropower, supporting the economics of potential development opportunities. The project is also supported by nearby commercial airports and significant cities (Loja) and enjoys strong community support.
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.
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
Surface and drill core samples from Brama were sent to the LAC y Asociados Cia. Ltda. Sample Preparation Facility in Cuenca, Ecuador for sample preparation. The standard sample preparation for drill core samples (Code PRP-910) is: Drying the sample, crushing to size fraction 70% <2mm and splitting the sample to a 1000g portion by riffle or Boyd rotary splitter. The 1000g sample is then pulverised to >85% passing 75 microns and then sent to the MSALABS in Langley, BC, Canada for gold and base metal analysis.
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-230 is considered a near total 4 acid technique using a 0.25g 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. MSALABS is an internationally accredited laboratory that has all its internal procedures heavily scrutinized in order to maintain their accreditation. MSALABS is accredited to ISO/IEC 17025-2017 Accredited Methods and certified to ISO 9001-2015.
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 9001-2015 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 MSALABS, an ISO/IEC 17025-2017 Accredited Method company and ISO 9001-2015 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)
MSALABS 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.
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 20.8% 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 6.85% 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:
Mario Drolet; Email: Mario@mi3.ca; Tel. (514) 904-1333
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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 anti-mining sentiment in certain regions of Ecuador, or 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,
President and CEO
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