Cobre del Mayo, S.A. de C.V. Announces the Completion of an Updated NI 43-101 Technical Report

MEXICO CITY, Dec. 16, 2015 /PRNewswire/ -- Further to the Press Release of December 14, 2015, wherein Cobre del Mayo, S.A. de C.V. ("CDM") announced the completion of an updated NI 43-101 mineral reserve and resource report for the Piedras Verdes copper operation (the "Technical Report") dated December 12, 2015, some bondholders asked with respect to the copper price deck used for evaluation. While this information was included in the 43-101 Report, for ease of reference we are reissuing this press release including this information, and it replaces the previous one.

Cobre del Mayo, S.A. de C.V. ("CDM") announces the completion of an updated NI 43-101 mineral reserve and resource report for the Piedras Verdes copper operation (the "Technical Report") dated December 12, 2015. This Technical Report, prepared by MICON International and AGP Mining Consultants, considers both the CDM leaching operations and the copper concentrate operations run by Kupari Metals (jointly, "PV Operations"). The effective date of the report is November 1 2015.

This report will not be filed with any securities commission or supervisor. It is not a public document and is available only to its Regulation S bondholders through the password protected Investors Section of its website.

NI 43-101 PV Operations Highlights:

• Estimated Measured and Indicated Mineral Resources of 452.8 Mt of ore at an average grade of 0.28% TCu. Equivalent to 1,266 kt of copper contained.

Note: The estimation uses the October 27, 2015, topographic surface and includes only material inside the June 2015 MRMR resource shell. The numbers may not add up due to rounding. The Measured and Indicated Mineral Resources are inclusive of those Mineral Resources modified to produce the Mineral Reserves. Cut-off grades used for resources are 0.1%TCu for oxides and secondary sulphides and 0.2%TCu for primary coppers. The resource has been constrained with an LG pit shell developed at $3.50/lb copper.

• Estimated Mineral Reserves of 291.8 Mt of ore at an average grade of 0.29% TCu equivalent to 846 kt of copper contained in ore

Notes: 1. Mineral Reserves are stated at a $0.01/t net value cut-off. Mineral Reserves are defined within a mine plan, with phase designs guided by LG pit shells, generated using measured and indicated material and a metal price of $2.80/lb Cu. The mining cost applied was $1.18/t with haulage cost adjustments for depth and destination. The flotation process plus G&A cost is $11.60/t. The total operating costs for Crush Leaching are variable but average $2.50/t, with an additional $0.36/lb of recovered copper for SXEW and $0.25/lb for G&A. The total operating costs for ROM Leaching are variable but average $1.07/t, with an additional $0.36/lb of recovered Cu for SXEW and $0.25/lb for G&A. Interramp slope angles varied from 38° to 43°. Recoveries applied were 45% for ROM leaching, 65% for crushed leaching, and 81% for flotation. 2. Tonnages are reported in metric units and are rounded to the nearest 10,000 tonnes and the TCu grade is rounded to two decimal places. Rounding as required by reporting guidelines may result in apparent summation differences.

The production and economic forecast highlights are as follows:

• The copper price book used for the financial analysis was as follows:

• Estimated Life of Mine (LOM) of 14 years, with a start date of beginning of 2016
• Cut-offs and Cut-over grades are based on NSR calculations which are nominally equivalent to:

• Average production from 2016 to 2026 of 38.7 kt/yr (of copper cathode and copper contained in concentrate), declining gradually as mining ends in 2030 and until leach out period is completed
• LOM C1 Cash Costs for the PV Operations of $US 1.78/lb (excluding royalties)
• Sustaining LOM Capital Costs for the PV Operations of $US 212 M.
• Unleveraged Net Present Value at 12% discount rate of $US 183 M for PV Operations

43-101 CDM Highlights:

Based on the Technical Report and removing the effects of Kupari Metals the following we have estimated the following summary data for CDM:

• Average copper cathode production from 2016 to 2026 of 28.5 kt/yr declining gradually throughout 2034
• Average ore for concentrate sold to Kupari from 2016 to 2026 of 2,055 kt/yr at an average grade of 0.52% TCu
• LOM C1 cash cost (including by-product credits from the sales of ore to Kupari Metals) of $US 1.77/lb.
• Unleveraged Net Present Value at a 12% discount rate of $US 110 M.

Qualified Persons:

The primary authors of this Technical Report are:

• William J. Lewis, B.Sc., P.Geo. a Senior Geologist with Micon based out of Toronto, Canada.
• Lyn Jones, P.Eng, Senior Process Engineer, AGP Mining Consultants, Inc.
• Jay Melnyk, P.Eng, Principal Mining Engineer, AGP Mining Consultants, Inc.

The technical information in this news release ("Technical Information") was prepared by, or under the supervision of, a qualified person (a "Qualified Person") as defined in National Instrument 43-101 Standards of Disclosure for Mineral Projects of the Canadian Securities Administrators ("NI 43-101"). The disclosure of the Technical Information contained in this news release has been reviewed and approved by Mark Pearson, P. Eng., President Frontera Mining and Cobre del Mayo's Chief Operating Officer, a Qualified Person under NI 43-101.

The complete document is available in the Investors section of Cobre del Mayo's website. Access to this section will require a username and password that can be requested from the following email address: ir@cobredelmayo.com.mx.

Related Links

http://www.cobredelmayo.com