In 2012, Mirasol staked a large land package containing nine projects in the newly discovered Gorbea Belt, securing an area with broad prospective alteration systems identified by its generative team. Detailed ground follow-up of these targets identified large outcropping gold systems at the Atlas and Titan projects.
After some initial work completed by Mirasol, the Gorbea package was optioned to Yamana Gold from 2015 to 2018. During this period, Yamana spent more than C$10M in exploration expenditures and drilled more than 11,000m on the project. In early 2019, Mirasol entered into a new agreement with Newcrest Mining to further advance exploration on this property package. Since the beginning of this exploration partnership, Newcrest has completed a total of 5,426m and reported exploration expenditures of approximately US$ 8.6 million on the property (to March 31, 2020), representing a significant investment on the project.
On January 28, 2019, the Company announced that it signed a definitive Letter Agreement for an Option and Farm-in Agreement with a subsidiary of Newcrest Mining Limited (Newcrest) for the Gorbea gold project in Chile. Newcrest has the right to acquire, in multiple stages, up to 75% of the Gorbea Project by completing a series of exploration and development milestones and making staged option payments to Mirasol.
Newcrest has completed its initial commitment to spend US$4 million and complete 3,000 m of drilling over an initial 18-month period. However, with exploration activities currently suspended at the site as a safety precaution due to the COVID-19 pandemic, Newcrest and Mirasol have agreed to extend the option period by 6 months to January 25, 2021 and Newcrest has committed to drilling at least 2,000m at the project over the upcoming season.
Upon Newcrest earning 75% of the Project, Mirasol can elect to fund its share and retain a 25% project equity position, or exercise a one-time equity conversion option to convert up to 10% of its equity into a NSR royalty at a rate of 2.5% equity per 0.5% NSR royalty (max 2% NSR royalty).
The Gorbea belt comprises of nine 100%-owned claim blocks totalling 32,000 ha and includes the Atlas and Titan prospects. The Atlas project is centred on a +20 km2 HSE gold alteration system hosting multiple gold and silver targets and contains many of the key geological, mineralization features and area extent to other economic systems in the area, such as Salares Norte (Gold Fields), Alturas (Barrick Gold) and La Coipa (Kinross Gold)., supporting its potential to host large-scale gold mineralization.
The latest round of drilling on the Atlas project, brings the total drilling to 15,925m in 35 holes by both Newcrest and Mirasol’s previous partner, and demonstrates widespread mineralization within the central breccia complex. In addition, lithochemical studies on drill samples indicate that the geochemical footprint is larger than the area covered by the drilling to date and is open to the north, east and southwest.
During the first half of 2019, Newcrest as operator of the Gorbea exploration program, completed two diamond drill holes for 903m, 50km of CSAMT geophysics over the Atlas target as well as reconnaissance mapping and sampling over several other target areas in the Gorbea property package.
Drilling was initially targeting a coincident geophysical, geochemical and alteration anomaly at depth below a barren steam-heated leach cap, following up on previous drilling results.
During the 2019/2020 field season, Newcrest completed 9 additional drill holes at the Atlas target, for a total of 4,523 m of diamond drilling this season.
Best Results from this season include:
ATL-DDH-001A: 0.52 g/t Au and 6.81 g/t Ag over 164m (from 372m), including:
1.07 g/t Au and 7.18 g/t Ag over 14m (from 372m), and
1.31 g/t Au and 7.82 g/t Ag over 16.5m (from 402.5m)
ATL-DDH-010: 0.54 g/t Au and 2.65 g/t Ag over 129m (from 363m), including :
1.4 g/t Au and 2.08 g/t Ag over 17m (from 364m), also including :
2.09 g/t Au and 3.00 g/t Ag over 10m (from 371m)
1.84 g/t Au and 3.57 g/t Ag over 3m (from 425m)
Mineralization encountered to date is associated with phreatomagmatic and hydrothermal breccias and intensely advanced argillically altered porphyritic andesite, often where a vuggy silica texture has developed. The area has been deeply oxidized to depths of over 400m, which is potentially advantageous for the development of favorable metallurgy.
Initial wide spaced drilling has been important to test the large size of the system and distribution of favorable outcropping breccia targets. Future efforts to define higher grade zones will now be guided by targeting resistive units identified by CSAMT geophysics along with structural mapping, geochemistry, and vectors to feeder zones from alteration zonation and alunite composition.
Mirasol continues to work closely with Newcrest to better understand the controls on the higher-grade mineralization and to collaborate in the definition of quality targets for future drilling, which is scheduled to restart in the southern hemisphere spring season of 2020.
In addition, Newcrest intends to drill-test the El Dorado prospect as well as continue field evaluation work at selected regional prospects (Ventura, Sirio, Orion and Titan).
During the three years of exploration at Gorbea, Yamana focused its drilling activity exclusively on the Atlas and Titan projects. The best drilling results on the Atlas project were received in 2017 from holes 15 and 16:
CLATDH0015: 1.07 g/t Au and 1.78 g/t Ag over 114.1m (from 347m), including:
36 m at 2.49 g/t Au and 3.08 g/t Ag
CLATDH0016: 0.32 g/t Au and 0.81 g/t Ag over 45.8m
To learn more about the project and recent exploration results see all Current and Historical News Releases.