Patriot Gold Corp., a developing gold and silver production and exploration company, today announced the results of a Preliminary Economic Assessment ("PEA") for the Moss Mine Project, located in the historic and active Oatman mining district near Bullhead City, Arizona.
Based on the recently announced updated resource estimate and an independent technical report co-authored by CDM Smith, Inc. ("CDM") and Metal Mining Consultants Inc. ("MMC") dated March 13, 2013 (the "Technical Report"), the PEA provides an evaluation of the economics of open pit mining and heap leach processing in Phase I and Phase II production for the Moss Mine Project.
Phase II Preliminary Economic Assessment Highlights*:
- Mine life of five years, 5,000 tpd, 42,000 AuEq oz/yr
- Pre-tax IRR of 117.9%
- Pre-tax payback of 15 months
- Pre-tax NPV @5% $110 million
- Capital expenditures $26.6 million
- Capital/average annual AuEq oz production $633/oz
- Cash Costs/AuEq oz $490/oz
- Metallurgical recoveries of 75-85% for gold and 55-77% for silver
"We are pleased with the outcome of the Preliminary Economic Assessment which not only supports the strong economic potential of the Moss Mine Project, but also provides sound guidance to the next phases of operations," said Bob Coale, CEO of Patriot Gold. "We believe that there continues to be upside in maximizing results from the in-field operations during the Pilot Plant operations phase (Phase I), from possible pit expansions as a result of the mine exploration programs and of course, possible Mine Life Extension or Expansion (Phase III). With the PEA results guiding our way, we remain very optimistic on the Moss Mine Project outlook and look forward to keeping our shareholders informed on our progress throughout the next critical phases of operations."
The Three-Phase Mine Development Plan, as outlined in previous news releases, is designed to move the Moss Mine Project forward in a defined and thoughtful manner - from conceptual design and laboratory test work to on-site pilot plant testing (Pilot Plant - Phase I) and then onto operations (Phase II). Phase II is independent from Pilot Plant - Phase I, and will only proceed if Phase I is successful. Phase III is conceptual only, will depend on the success of Phase II, and so is not included in the PEA. Phase III would involve mine life extension and/or expansion of production volumes.
A summary of the key parameters and results of the PEA follow.
Pilot Plant - Phase I
- Designed to in-field demonstrate the economic and technical viability of heap leach processing
- Includes pilot-scale open pit mining and heap leach processing of an aggregate of approximately 90,000 tonnes of mineralized rock
- All activities would be confined to patented property
- Low strip ratio 0.79:1
- Mined zone approximately 500 feet in length
- Both higher grade and lower grade material will be tested in Pilot Plant - Phase I
- Production rate of 1,000 tonnes of mineralized rock / day
- Mining and processing activities to be performed by contractors
- Provision of a 67,463 tonne stockpile of mineralized rock for Phase II production
- Will proceed upon determination of successful results from Pilot Plant - Phase I
- Would include mining and processing of approximately 6.13 million tonnes of mineralized rock
- Open pit mining methods and heap leach processing
- Low strip ratio 1.6:1
- All activities would be confined to patented property
- Pit depth ranges from 30 feet to 575 feet
- Production and processing activities are expected to be 5,000 tonnes of mineralized rock / day
- Mining activities to be performed by contractors and processing activities to be performed by Northern Vertex
New Technical Report on Resources:
An updated independent technical resource estimate was prepared by Dr. Stewart D. Redwood, FIMM, and Scott Wilson of MMC and was outlined in a news release dated March 26, 2013. The summarized resource estimate in the table below includes 12.6 million tonnes (AuEq of 1.03 g/t) of measured resources and 9.98 million tonnes (AuEq of 0.73 g/t) of indicated resources (aggregate average: 22,589,000 tonnes at 0.90 AuEq g/t) for total measured and indicated AuEq oz of 653,600 (537,000 Au oz and 5,830,000 Ag oz). It is important to note that mineral resources described herein are not mineral reserves and, as such, may not have demonstrated economic viability.
Resource Estimates Used for Economic Assessments in the PEA:
Resources used in the economic assessment for the Moss Mine Gold-Silver Project Phase I Pilot Plant and Phase II Operations are as follows:
Resource Estimates for Phase III - Mine Life Expansion / Extension:
The anticipated operating period for Phase I is 15 months and for Phase II is five years, including development and construction. As previously stated, Phase II will only proceed upon the successful completion of Phase I.
Pilot Plant - Phase I and operations - Phase II measured and indicated resources encompass 265,000 of the total 654,000 ounces gold equivalent of global resources estimated by MMC. Upon the completion of Phase II, 389,000 ozAuEq will remain. Extending mining and processing operations onto unpatented land by mining along strike and to depth has the potential to significantly extend the life of the mine. This will be the subject of further investigation concurrent with Phase II operations. This investigation will incorporate permitting, technical, economic, and financial elements into one or more pre-feasibility and/or feasibility studies.
It should be noted that the Phase I and Phase II resources described are physically constrained to that which can be reasonably extracted by limiting mining and related facilities to patented - or private - land. The conceptual Phase III mine plan would be pursued without the physical constraints of limiting operations to patented land and will require normal course approvals from various US governmental departments and mining authorities.
Based on development of the initial resource solids containing the Phase I and Phase II resources, the mining extraction recovery rate of the in-situ resource is anticipated to be 100 percent.
Overall metallurgical data shows that ore from the Moss Mine Gold-Silver Project is readily amenable to agglomeration/heap leach cyanidation processing. Column test recoveries obtained from the bulk samples, finely crushed using rolls crushers and agglomerated using cement as a binder, ranged from 75% to 84.6% for gold and from 61.3% to 76.6% for silver. Recovery percentages are summarized in the table below:
Gold extraction was still in progress when column leach tests were terminated for purposes of completing the PEA and is expected to increase further with a longer leach cycle. Preliminary data from an ongoing column leach test indicate that the low grade mineralization will be amenable to agglomeration/heap leach cyanidation processing after roll crushing to a 95%-1/4" feed size. Use of industrial scale high pressure grinding rolls (HPGR) has the potential to improve liberation and yield higher recoveries.
The favorable results from the labatory metallurgical testing provide the basis for proceeding with the proposed field testing Pilot Plant - Phase I. Metallurgical data from the Pilot Plant program will be collected and analyzed for use in the design of operations - Phase II. Both higher grade and lower grade mineralized rock is expected to be tested in the Pilot Plant. Although positive results have been obtained to date, additional metallurgical test work will be required. Consequently, recoveries used in the PEA have been conservatively scaled back to 75% for Au and to 55% for Ag.
The Preliminary Economic Assessment recommends a continued exploration program to further delineate the mineralization at the Moss Gold-Silver Project. The limits of mineralization are still open at depth and to the west. The recommended drilling program includes additional drilling of 2,200 meters and associated costs are outlined in the table below:
Production and Economic Criteria:
The key Production and Economic Criteria outlined in the PEA are as follows:
The following table shows the variances to the Net Present Value (NPV) and Internal Rate of Return (IRR) from the base case of $1500 gold and $30/oz silver.
Various other sensitivities have been carried out assessing the effects of:
- An increase in capital cost by $10 million
- An increase in operating costs by 20%
- An increase in gold and silver recovery rates to match higher recovery rates in lab results
- An increase in costs of diesel fuel for power production by $1 per gallon
- A decrease in capital equipment costs by 25% by way of using used equipment instead of new
- An increase in pit slope from 55 degrees to 65 degrees
- A decrease in delay of NSR receipts from 25% to 10%
The Moss Mine Project & Patriot Gold's Optionee/Operator
The Moss Mine Project is located approximately seven miles due east of Bullhead City, Arizona. Patriot Gold is the 100% owner in the historic Moss Gold-Silver property located in Mohave County, Arizona, which is subject to certain royalties and an earn-in option agreement for 70% interest. The earn-in optionee/operator has the right to earn a 70% interest in the project by completing an $8.5 million investment over five years and a bankable feasibility study. Subsequent to the optionee/operator earn-in, financing of the project will be on a proportional basis.
Disclaimer: This announcement may contain forward-looking statements which involve risks and uncertainties that include, among others, limited operating history, limited access to operating capital, factors detailed in the accuracy of geological and geophysical results including drilling and assay reports; the ability to close the acquisition of mineral exploration properties, and other factors which may cause the actual results, performance or achievements of the company to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. More information is included in the company's filings with the Securities and Exchange Commission, and may be accessed through the SEC's web site at http://www.sec.gov.