Drilling returns 202m at 0.88g/t gold equivalent (from 148m) at Bramaderos gold-copper project, Ecuador
OTTAWA, Aug. 30, 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:
https://cornerstoneresources.com/site/assets/files/5868/nr22-21figures.pdf.
HIGHLIGHTS:
- Exceptional intersection demonstrates the scale and strong grade of the Brama-Alba porphyry discovery; Assays from hole BMDD034 include:
- 202m at 0.88g/t AuEq* (0.65g/t gold and 0.13% copper), from 148m in BMDD034, including
- 42.0m at 1.00g/t AuEq1 (0.74g/t gold, 0.14% copper), from 252m
- 42.0m at 1.00g/t AuEq1 (0.74g/t gold, 0.14% copper), from 252m
- 202m at 0.88g/t AuEq* (0.65g/t gold and 0.13% copper), from 148m in BMDD034, including
- These assays sit within a broader interval of 363m at 0.71g/t AuEq* from 124m in BMDD034
- The area of mineralization near BMDD034 remains open
- These results provide further evidence that the Brama-Alba discovery is large by global standards and contains grades in line with many well-known porphyry projects
- Exploration continues at nearby porphyry targets Playas, Sandia, Melonal, and Limon in preparation for drilling in 2022
Sunstone Managing Director, Malcolm Norris, said:
“This is a very good intersection in BMDD034 with width and strong grade and will be included in our upcoming initial Mineral Resource Estimate (MRE).
“It is clear we have a large gold-copper porphyry system at the Alba end of the 1.2km long Brama-Alba porphyry deposit, which remains open in several directions.
“It is also worthy to note that the gold equivalent calculation is based on gold and copper only, and yet we are seeing very consistent silver values through all mineralized drill holes, as well as domains of elevated molybdenum.
“We have four drilling rigs working 24/7 at Brama-Alba so that we have adequate drill coverage to deliver the initial MRE in the 4th quarter. The initial MRE for Brama-Alba will be a starting point that we can then build on.
“We are working up multiple adjacent targets for drilling so that we can also deliver an Exploration Target, and position Sunstone and Cornerstone to deliver additional discoveries at Bramaderos during 2022. These will be high value discoveries because they will enable expansion of whatever initial MRE is delivered.”
* 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.
FURTHER INFORMATION:
The results from hole BMDD034 expand the size of the Alba discovery with a wide higher-grade intersection of 202m at 0.88g/t gold equivalent with sub-domains that exceed 1.0g/t gold equivalent (see Table 1 below). The wide interval of 202m at 0.88g/t gold equivalent is within a broader interval of 363m at 0.71g/t gold equivalent.
All holes reported in this release intersected significant wide zones of gold-copper mineralization (Table 1). Results from holes BMDD017, 020, and 021 were previously reported (see news releases dated January 20, 2022, March 7, 2022, and June 1, 2022), and post reporting these holes were extended to test for deeper mineralization in these areas. BMDD017 extended low grade mineralization by 80m to 463m.
Drill hole BMDD034 had a shallow dip of -30 degrees and therefore this strong intersection is within 150m of surface (Figure 4). The intersection in BMDD034 is orthogonal to well mineralized previously reported holes BMDD020 and 021 (Table 1, Figure 4) and therefore helps define a higher grade, wider zone of mineralization at Alba.
The results provide further evidence that the Brama-Alba porphyry system hosts a substantial gold-copper porphyry deposit (Figures 3, 4, 5).
The Brama-Alba system remains open in several directions, and these areas are being tested as part of the current drilling program (Figures 3 and 4). Adjacent targets with the potential for new discoveries include Playas to the east, Sandia to the south, Limon to the north, and Melonal to the west (Figure 5) and are expected to be drill tested in 2022, once the resource drilling at Brama-Alba is complete in late September.
Assay results for drill holes BMDD017, 20 and 21 extensions, and 033 and 034 are provided in Table 1 and shown in Figures 3, 4, and 5.
Table 1: Summary of mineralized intersections in Brama drill holes BMDD017, 20, 21 extensions, and BMDD033 and 034.
| Drill Hole | EOH (m) | From (m) | To (m) | Interval (m) | AuEq (g/t) | Au (g/t) | Cu (%) | Mo (ppm) | Ag (g/t) |
| BMDD017 | 616.77 | 0.00 | 308.00 | 308.00 | 0.48 | 0.27 | 0.12 | 3.8 | 1.5 |
| incl | 0.00 | 84.00 | 84.00 | 0.79 | 0.50 | 0.16 | 4.3 | 2.2 | |
| incl | 10.50 | 48.00 | 37.50 | 0.98 | 0.65 | 0.18 | 4.5 | 2.2 | |
| 378.00 | 463.00 | 85.00 | 0.34 | 0.15 | 0.11 | 9.5 | 1.7 | ||
| original hole drilled to 383.63m; then extended to 616.77m | |||||||||
| BMDD020 | 359.73 | 95.00 | 359.73 | 264.73 | 0.71 | 0.49 | 0.13 | 29.0 | 1.3 |
| incl | 119.00 | 139.00 | 20.00 | 0.99 | 0.91 | 0.04 | 32.6 | 0.51 | |
| incl | 126.00 | 133.00 | 7.00 | 1.87 | 1.77 | 0.05 | 27.1 | 0.7 | |
| original hole drilled to 359.73; then extended to 494.02m | |||||||||
| BMDD021 | 407.64 | 107.6 | 331.3 | 223.7 | 0.81 | 0.58 | 0.13 | 40.9 | 1.2 |
| incl | 135.0 | 272.4 | 137.4 | 1.05 | 0.75 | 0.17 | 51 | 1.4 | |
| incl | 136.0 | 196.7 | 60.7 | 1.35 | 1.01 | 0.19 | 73.3 | 1.5 | |
| and | 219.8 | 234.4 | 14.6 | 1.20 | 0.85 | 0.2 | 48.8 | 1.5 | |
| original hole drilled to 407.64m; then extended to 601.75m | |||||||||
| BMDD033 | 331.34 | 86.40 | 331.34 | 244.94 | 0.48 | 0.32 | 0.09 | 20.7 | 1.2 |
| incl | 244.12 | 270.00 | 25.88 | 0.74 | 0.56 | 0.10 | 47.9 | 1.2 | |
| and | 306.00 | 331.34 | 25.34 | 0.73 | 0.56 | 0.09 | 32.0 | 1.3 | |
| BMDD034 | 587.47 | 124.00 | 487.00 | 363.00 | 0.71 | 0.51 | 0.12 | 31.4 | 1.1 |
| incl | 148.00 | 350.00 | 202.00 | 0.88 | 0.65 | 0.13 | 46.9 | 1.1 | |
| incl | 156.00 | 178.00 | 22.00 | 1.04 | 0.86 | 0.10 | 92.2 | 0.9 | |
| and | 252.00 | 294.00 | 42.00 | 1.00 | 0.74 | 0.14 | 38.0 | 1.2 | |
Note that original drill hole intersections for BMDD017, 020, and 021 were reported previously (see news releases January 20, 2022, March 7, 2022, and June 1, 2022). The holes were extended and drilled low grade mineralization and in the case of BMDD017 extended the >0.3g/t AuEq mineralized interval by 80m to 463m.
About Bramaderos
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 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.
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
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.
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 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:
Investor Relations:
Mario Drolet; Email: Mario@mi3.ca; 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 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,
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 The gold equivalent calculation formula is AuEq(g/t) = Au(g/t) + Cu% x 1.77. The prices used were US$1,770/oz gold and US$9,750/t copper, and A$:US$0.70. Recoveries are estimated at 89% for gold and 86% for copper from metallurgical studies. In JV partner and project operator Sunstone’s opinion all the elements included in the metal equivalents calculation have reasonable potential to be recovered and sold.
