Gorbea Gold Belt


Joint Venture

A modern day “gold rush” is now underway in the Mio-Pliocene age volcanic arc in northern Chile and Argentina that is driven by new exploration models and technology targeting multi-million ounce high sulfidation epithermal (HSE) oxide gold deposits.  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. These oxide gold systems were not recognized by previous explorers and underscores how Mirasol’s industry-leading approach to exploration methods delivers opportunities for shareholders.

A joint venture with Yamana Gold was signed in March 2015 with an option to acquire 75% interest over a seven-year period. Yamana has demonstrated a commitment to an aggressive exploration program where the first earn-in option to 51% requires US$10 million in exploration spending and cash payments to Mirasol of US$2 million over four years. Included in the deal is provision for Yamana to provide financing to Mirasol for its 25% share of the development costs and the option for Mirasol to convert up to 9% of its equity position into a 3% net smelter return ("NSR") royalty. Yamana completed its 2nd drilling program in 2017 and entered the 3rd year of JV in May 2017 making a US$ 400,000 option payment to Mirasol.

Project Details

The Gorbea belt comprises of nine 100%-owned claim blocks totalling approximately 23,080 ha and includes the Atlas and Titan projects. The Atlas project is centred on a +25 sq. km HSE gold alteration system hosting multiple gold and silver targets that are being drill tested by Yamana.

Best results to date were received in 2017 from holes 15 and 16 and include:

  • 114.1 m at 1.07 g/t Au and 1.78 g/t Ag,
    • including 36 m at 2.49 g/t Au and 3.08 g/t Ag (hole 15)
  • 45.8 m at 0.32 g/t Au and 0.81 g/t Ag (hole 16)

The intersection in hole 15 starts from 347 m down hole.  Hole 16 is interpreted to have drilled across the top of this same breccia body.

The current drilling at Atlas has outlined gold mineralization (the “Steam Heated Zone”) in an area of 650 m by 125 m by over a 200 m vertical interval. The Steam Heated Zone may represent a body of gold and silver mineralization that as defined to date is open to depth and laterally in all directions outside the area of current drilling. As currently known, the top of mineralization is located between approximately 255 to 310 m depth beneath altered cap rocks, which is a characteristic in-common with other recent, HSE gold discoveries elsewhere on this same mineral belt in Chile.

Although the intersections returned from the program to date are relatively deep, the geometry of the surface soil anomaly, distribution of un-explained stream sediment gold anomalies and alteration, suggest the target zone may extend to the south where topography is more favourable, highlighting the possibility for mineralization to occur closer to surface in this area.

Drill holes 15 and 16 were drilled toward each other (“scissor holes”) from the NW and SE to cross each other at depth, testing a zone beneath an area of coincident outcropping breccia, weakly anomalous soil geochemistry and a geophysical anomaly that lies midway between drill holes 7 and 10 from last season’s drilling.  Holes 7 and 10 returned the best results from the 2015-16 drill campaign including 40 m at 1.38 g/t Au, with 28 m at 1.82 g/t Au.  The mineralization at Atlas is interpreted to be oxidized to depths of more than 400 m downhole.  Deep oxidation is considered a positive feature at Atlas as it may suggest the potential for favourable metallurgical characteristics of the mineralization at the project.

Total drilling completed since inception of the Gorbea JV in May 2015 is over 8,704 m, and Yamana’s total exploration spend to May 2017 is approximately US$5.2M, against the US$10 M required to trigger the 51% earn-in milestone over a maximum of 4 years. Yamana also advised Mirasol that it has increased its 2017 Gorbea JV exploration budget by an additional US$700,000.   The additional exploration funds will be directed to drilling at the Atlas Steam Heated Zone and other new targets at the project. Yamana is planning to re-commence drilling at Atlas for the southern hemisphere 2017 spring field season.

Atlas contains many of the key geological and mineralization features of recent multi-million-ounce discoveries at Alturas (Barrick Gold) and Salares Norte (Gold Fields), supporting its potential to host large-scale gold mineralization.

The Gorbea Belt project is part of Mirasol’s generative program strategy to search for standalone multi-million-ounce oxide bulk-minable discoveries.

To learn more about the Yamana JV and recent drilling results see all Current and Historical News Releases below. To learn more about HSE systems see Further Information below.

Gorbea rock chip sampling

Gorbea field sampling

Gorbea mapping

Gorbea steam heated native sulphur

Gorbea field camp

Atlas Project vista

Atlas Project trenching

Atlas Project jigsaw breccia with up to 1.09 gt Au in TR-02

Atlas Project late stage barite vein common in vuggy silica structures from 3.27-8.85 gt Au

Atlas Project vuggy silica after porphyritic andesite with up to 7.28 gt Au and 5.77 gt Ag

Atlas Project core logging

Atlas Project MRZ core silicified breccia

Titan Project mapping

Titan Trenches

Titan Project trenches overview

Titan Project MRZ drilling

In Portfolios