Exploratory drilling at the Los Helados copper-gold prospect on the Chile/Argentina border. (Photo: NGEx)
NGEx Resources is conducting a preliminary economic assessment (PEA) of the potential for integrated development of the Los Helados and Josemaria copper-gold deposits, located about 12 km from each other on opposites sides of the Chile/Argentina border. Los Helados is located in Region III, Chile; Josemaria is located in San Juan province, Argentina.
NGEx has a 60% interest in each project. Pan Pacific Copper holds the remaining 40% of Los Helados, while Japan Oil, Gas, and Metals National Corp. (JOGMEC) holds the remaining 40% of Josemaria.
The current PEA of an integrated project is building on a 2014 PEA of stand-alone development of Los Helados. The stand-alone scenario called for development of a block-cave underground mine at Los Helados, producing up to 130,000 metric tons per day (mt/d) of ore and an average of 115,000 mt/y of copper, 133,000 oz/y of gold, and 675,000 oz/y of silver in concentrates. Mine life was forecast at up to 26 years, depending on the production rate.
The current integrated study will consider a scenario in which production from both Los Helados and Josemaria will feed a central processing facility, with a goal of optimizing overall project economics. NGEx expects to complete the integrated project PEA in early 2016.
NGEx President and CEO Wojtek Wodzicki said, “Our current study is focused on trying to significantly reduce pre-production timelines by staging development of Josemaria and Los Helados to enable early delivery of the highest-grade and most easily accessible material to a central processing facility. This approach, combined with the potential to reduce capital costs and spread them over a larger resource base, has the potential to create a very exciting project. The tremendous exploration upside we continue to see on our land package adds a further dimension to this emerging district and has the potential to yield additional discoveries over time.”
Ongoing work in 2015 includes additional metallurgical testwork on both deposits to improve metal recoveries and concentrate grades and to better understand how these will vary over the life of the proposed mine; geotechnical studies at Los Helados to better define the block cave mining characteristics of the deposit; an evaluation of the optimum site for a centralized processing plant, including an assessment of options to reduce the infrastructure, water and power costs used in the Los Helados PEA; and environmental baseline studies.
In addition to the ongoing engineering studies, NGEX has recently completed a comprehensive review of the exploration potential on the approximately 60,000-ha land package that encompasses the Los Helados and Josemaria deposits, as well as its 100% owned Filo del Sol deposit. A comprehensive surface exploration program has been developed for the upcoming field season from January through to April 2016. Work will be focused on geological mapping, geophysics, and geochemical sampling to follow up on numerous areas of previously identified porphyry-style alteration. This work is expected to lead to the definition of multiple drill targets that will be tested at a later date.