Drill targets defined at the Espejo Project within the ENAMI EP Strategic Exploration Alliance in NW Ecuador - Seite 2

Following various community & social responsibility outreach processes carried out by CESA and ENAMI with regional and local authorities and communities, systematic exploration surveys were implemented starting in Q3 of 2017. Several prospective zones were defined at Espejo and at the Rio Magdalena Project and initial results released on February 27, 2020 (NR 20-05: https://cornerstoneresources.com/news-releases/20-05-high-potential-po ...).

A few weeks following that announcement, field work on the projects was suspended due to the Covid 19 sanitary crisis from March to October 2020 to protect Cornerstone employees, providers and communities from possible infection. In coordination with Ecuador’s health and mining authorities, a Covid 19 management protocol was designed, tested and implemented. This protocol is ongoing since then and will be maintained as long as necessary. As part of Cornerstone’s Corporate Social Responsibility policy, strong support was provided to local communities and authorities to prevent contamination, including sanitary training, provision of sanitary equipment and testing.

In November 2020, exploration work was restarted at Espejo. Data processing and prospecting work was carried out at anomalies #1 and #2 (refer to NR 20-05). Soil sampling grids were extended to cover the full extension of the previously defined geochemical anomalies and detailed geological mapping was carried out to support geological modeling. To date, 956 rock samples, 3039 soil samples and 629 stream sediment samples have been collected on the Espejo project. A regional U/Pb age dating and a detailed geochemical (major, trace and REE elements) program was started in the last two months with the objective to define and characterize intrusive complexes source of porphyry style mineralization in this part of the country. Preliminary (and incomplete) data indicate an age varying from 8.9 to 7.7 Ma at Espejo for intrusives associated to mineralization, similar in age to that found at the Llurimagua project (Schutte 2010) (Figure 1).

Anomaly ESP # 1

3D magnetic inversion modeling was carried out on target areas at Espejo. Data show a strong and extensive magnetic anomaly below the Cu-Mo (Au), 1.9km by 1.3km, ESP #1 rock and soil anomaly (Figures 2, 3 and 4). The geochemically anomalous zone is fully open to the NW where porphyry style mineralization and veining was found in the creeks some 500m in this direction. The SE-NW cross-section (Figure 5) shows the shape and large size of the multiple magnetic bodies that extend from surface to > 1500m below surface. Geological mapping indicates that these magnetic bodies are associated to an intrusive complex centered right below the anomalous zone. A Phase 1 drilling program (20 holes and 12,000 metres) was preliminarily defined and is shown on Figure 5. This planning will be refined in the coming months, once further mapping and sampling is completed.