Assays include 69.6m at 0.65g/t gold and 0.2% copper

Cornerstone Capital Resources Inc. (TSX-V: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 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:

https://cornerstoneresources.com/site/assets/files/5827/nr21-17figures.pdf.

HIGHLIGHTS:

• Strong assay results received for holes BMDD009, 010, and 011 at the Brama prospect:
  • BMDD009: 185.3m¹ at 0.4g/t gold, 0.15% copper, (0.64g/t gold equivalent AuEq²) from 116.8m
  • BMDD010: 170.65m at 0.46g/t gold and 0.15% copper. (0.7g/t AuEq) from 311.75m, including
    • 69.6m at 0.65g/t gold, 0.2% copper, (0.97g/t AuEq) from 347m
  • BMDD011: 404.8m at 0.32g/t gold, 0.09% copper, (0.46g/t AuEq) from surface, including
    • 51.3m at 0.54g/t gold, 0.07% copper (0.65g/t AuEq) from surface
• BMDD009 and 010 have further defined the gold-copper mineralized porphyry and intrusive breccia
• BMDD011 has extended the gold-copper mineralized domain to the northwest, below well mineralized trench sampling
• A detailed 3-D geological model has been built for Brama and will underpin a Mineral Resource Estimate (MRE) to be undertaken in early 2022
• Drilling is ongoing with six more holes planned as part of the maiden Mineral Resource drill program

FURTHER INFORMATION:

The results from holes BMDD009, 010 and 011 further highlight the potential for Brama to host a substantial gold-copper porphyry system (Figure 3).

In light of these results Sunstone has defined a drill program to continue through to December 2021, after which all data will be compiled and an initial Mineral Resource Estimate undertaken in early 2022.

Cornerstone VP Exploration, Yvan Crepeau, said:

“We are very pleased with the latest round of results which provide more firm evidence that Brama has the potential to be a large gold-copper mineralized porphyry. Importantly, we are seeing good gold-copper grades from surface.

“An initial Mineral Resource Estimate is a logical next step for the Brama target. Drilling is being guided by robust 3D geological modeling to continue to define the Brama system. In parallel we are re-visiting other targets such as Limon, Playas and Melonal (see Figure 2) with a view to defining additional resources.

“Our plan is to grow the scale of the opportunity at the Bramaderos Project via exploration and mineral resource definition across several porphyry systems.”

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 reader is cautioned that there has been insufficient exploration to define a mineral resource at Brama and it is uncertain if further exploration will result in the target being delineated as a mineral resource.

Discussion of Results

Drill hole BMDD009 was drilled in the east and central parts of the main Brama porphyry system (Figures 4 & 5) and intersected a veined porphyry system hosted by diorite. The drill hole further strengthened the interpretation of geology and mineralization between holes BMDD001 and 002.

Drill hole BMDD010 (Figures 4 & 5) intersected the main Brama porphyry stockwork style mineralization and the deeper northern part of the intrusive breccia intersected in BMDD008. The hole drilled orthogonal (at right angles) to previously drilled holes BMDD001, 002 and 005 and has better defined the higher-grade mineralization reported from BMDD001 and historical hole CURI-03, and from the intrusive breccia in hole BMDD005. Hole BMDD010 was drilled at a shallow dip of -30⁰ and therefore the intersections are between 200m and 300m below surface.

Drill hole BMDD011 was drilled towards the northwest from the collar of hole BMDD008 (Figures 4 & 5) and was sited to test the northwest up-dip continuation of the mineralized intrusive breccia body that was intersected at depth in BMDD008, and to test below well mineralized trench intervals of 70m at 0.68g/t gold and 0.16% copper, and 63m at 0.77g/t gold and minor copper.

Assays are pending for holes BMDD012 and 013. Both holes have tested magnetic anomalies to the northwest of the Brama area and have intersected mineralization.

BMDD014 has recently been completed and hole BMDD015 is in progress. Both are testing areas of limited drilling within the higher-grade intrusive breccia.

Table 1: Summary of mineralized intersections in Brama drill holes BMDD009, 010 and 011.

* Gold equivalent values are included in Table 1 to enable comparison, in general terms in an early-stage exploration context, to other large lower-grade gold systems, and to other porphyry systems that are often reported in metal-equivalent terms and are invariably gold and copper deposits, with both metals being targeted by exploration.

Exploration Program at Brama for the Remainder of 2021

Drilling will continue at the Brama target with 1 drill rig through to December 2021. During that period an additional 6 holes for 2,300m are planned to be completed.

This drilling program will form the basis for an maiden (initial) Mineral Resource Estimate (MRE) to be undertaken in early 2022. The goal of this MRE is to establish an initial near surface resource estimate that can then be expanded as exploration continues at Brama and the other nearby targets such as Limon and Melonal (Figure 2). At Brama the >0.4g/t gold equivalent domain is shown in Figure 3 extending from surface to a depth of ~500m as currently modeled and is open at depth. The domain is a plunging ovoid shape with dimensions of 460m (plunge) x 350m (long) x 220m (width).

Planning is also underway for an electrical geophysical survey over the Limon target in late 2021 to early 2022. It is expected that this program will define anomalies for further drill testing in areas where alteration has compromised the magnetic signature of the porphyry systems. The drill targets to be defined will be followed up in 2022. If the results of the survey are promising, then additional surveys may be undertaken at Brama Hill and other targets (Figure 2).

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.