Los Helados
| Deposit Type | Copper-Gold Porphyry |
| Indicated Resource* |
2.1 Bt @ 0.51% CuEq |
| Location | Region III, Chile 135km SE of Copiapo |
| Ownership | ~69% NGEX; ~31% Nippon Caserones Resources |
*see Resource Table for details
Summary
Los Helados is a copper-gold porphyry deposit discovered by Josemaria Resources inc. (formerly NGEx Resources Inc.) in 2008, and was spun-out to NGEx Minerals via a plan of arrangement in 2019. It is one of the largest grassroots copper-gold discoveries made in the last decade and is one of the largest undeveloped copper-gold resources in the world. The deposit is well located with respect to existing mining infrastructure at the Caserones Mine, where NGEx Minerals’ 31% partner at Los Helados also holds a minority interest. In addition, Los Helados is 10 km from the Lundin Group's Josemaria Project which is under development in neighbouring Argentina. Metallurgical test work indicates that Los Helados would produce a high-quality precious metal-rich copper concentrate. We believe that the combination of a large, high-quality resource with the proximity to mining infrastructure owned by our partners positions Los Helados as one of the best copper development opportunities globally.
Location
The Los Helados deposit is located in the Andes Mountains of Region III (Atacama Region), Chile, approximately 10 kilometres north of the Lunahuasi project located in the San Juan Province, Argentina. The approximate latitude and longitude centroid of the Los Helados deposit is 28.3408˚ S, 69.5857˚ W.
Access to both Lunahuasi and Los Helados can be made via Copiapó, Chile, a driving distance of about 177 kilometres, or from San Juan, Argentina, a total driving distance of approximately 264 kilometres.
The property is in a high altitude dry to arid climate, which is characterized by low temperatures throughout the year, typically below 15˚ C in the summer. Precipitation is almost always in the form of snow with most precipitation happening during the winter. The average annual precipitation is approximately 193 millimetres.
Exploration fieldwork is typically carried out from mid-October to early-May, although year-round operations would be possible with additional preparation.
Geology
Los Helados is a copper-gold (Cu-Au) porphyry deposit. Mineralization at Los Helados is primarily hosted by a Miocene magmatic–hydrothermal breccia that forms a roughly circular, pipe-like body with minimum dimensions of 1,100 m east–west, 1,200 m north–south, and at least 1,500 m vertically. The breccia body is surrounded by a broad halo of moderate to low grade Cu–Au mineralization which diminishes in grade with increasing distance from the breccia contact. The mineralization is dated at 13.13 ± 0.32 Ma.
Exploration Potential
The mineralization limits have been established by drilling to the west, east and south; however, the northern limit of the breccia body has not yet been defined and the system also remains open at depth. In particular, recent internal NGEx studies have suggested the presence of a discrete, higher-grade breccia phase occurring along the western and southwestern margins of the breccia. This high-grade breccia zone remains open for further expansion.
Resource
The Company’s most recent Mineral Resource estimate for the Los Helados Project, effective as of October 31, 2023, at a cut-off grade of 0.33% CuEq is comprised of 2.1 billion tonnes at 0.40% copper, 0.15 g/t gold and 1.5 g/t silver, containing 18.4 billion pounds of copper, 10.2 million ounces of gold and 97.5 million ounces of silver in the Indicated category, and an Inferred Mineral Resource estimate of 1.1 billion tonnes at 0.34% copper, 0.10 g/t gold and 1.4 g/t silver for 8.2 billion pounds of copper, 3.6 million ounces of gold and 50.2 million ounces of silver. The deposit contains a discrete higher grade core at a cut-off grade of 0.60% CuEq of 510 million tonnes of 0.56% copper, 0.21 g/t gold, 1.8 g/t silver for a CuEq grade of 0.72%.
Metallurgical Testwork
A two-phase metallurgical test work program for Los Helados was conducted at SGS Minerals S.A. (SGS) laboratories in Santiago, Chile under the supervision of Amec Foster Wheeler. Material from Los Helados was also tested for amenability to processing by High Pressure Grinding Rolls (HPGR) by Thyssenkrupp.
The testwork completed to date indicates Cu recovery ranges from 84.2% to 93.9%, gold recovery averages 76% and silver recovery averages 60%./p>
No deleterious elements were noted in the concentrates produced from the testwork completed on Los Helados mineralization and they are expected to be marketable to copper smelters around the world.
Ownership
NGEx currently holds an approximately 69% interest in Los Helados subject to a Joint Exploration Agreement with Nippon Caserones Resources which holds the remaining approximately 31%. NGEx is the operator of the Los Helados Project.
NGEx has a life-of-project lease agreement with the owners of the surface rights covering 20,000 hectares over the Los Helados Project area. This agreement secures the surface rights needed for all future exploration, development and mining.
History
Los Helados is a grassroots discovery made by the NGEx team in 2008. The initial discovery hole, LHDH004, returned a 762 metre interval grading 0.43% copper and 0.22 g/t gold. This was followed up by LHDH016 in 2010, which was the first hole into the deposit’s high-grade core, now known as the Condor Zone, returning 737 metres grading 0.64% copper and 0.30 g/t gold and LHDH017 in 2011, which revealed the true size of the deposit with a 1,090 metre interval grading 0.51% copper and 0.26 g/t gold.
Following a reinterpretation and revision to the Los Helados geological model, which illustrated the deposit’s potential for multiple, distinct high-grade centres, LHDH076 and LHDH078 drilled in early 2022 identified two additional high-grade structures, now named the Fenix and Alicanto Zones, respectively.
S&P Global Market Intelligence ranks Los Helados as the 4th largest copper deposit discovered globally between 2008 and 2017.