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United States

Mexican Hat Project

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Summary

Mine TypeOpen Pit
Study CompletedPreliminary Economic Assessment
Commodities
  • Gold
Mining Method
  • Truck & Shovel / Loader
Mine Life10 years (as of Jan 1, 2025)
SnapshotThe Mexican Hat Project hosts a shallow oxide gold resource characterized by excellent metallurgy and high recoveries.

The project design features two independent pits, each developed using a five-phase (pushback) mining approach.

Production strategy includes:
- Mine the South Pit first, as its shallow ore and lower stripping ratio support a faster production ramp-up.
- Stockpile lower-grade ore in the early years to prioritize higher-grade feed for the heap leach pad and maximize gold output.

The process plant is designed to produce gold doré bars.

The forward plan for Mexican Hat involves advancing the project to the Feasibility Study stage and progressing through the permitting process.

As of September 2025, environmental baseline studies are ongoing to support the upcoming permitting phase.
Latest NewsGMV Minerals Inc. Announces Updated PEA Results at Mexican Hat Gold Project in S.E. Arizona     August 13, 2025

Owners

SourceSource
CompanyInterestOwnership
GMV Minerals Inc. 100 % Indirect
GMV Minerals Inc. has 100% interest in the Mexican Hat Project.

Contractors

ContractorContractDescriptionRef. DateSource
Sulphur Springs Valley Electric Cooperative, Inc. Power supply Power will be supplied to the Project by the Sulphur Springs Valley Electric Cooperative (SSVEC). SSVEC services power in Cochise County for Mexican Hat region. SSVEC will extend an existing 69 kV powerline a distance about 12 km (7.5 miles) to the Project site for supplying a 6 MW load. SSVEC will be responsible for obtaining all right-of-way easements for the power line extension. Aug 8, 2025
unawarded or unknown Mining Contractors would be used for both mining. Aug 8, 2025
unawarded or unknown Crushing & Grinding The crushing plant will be supplied, operated, and maintained by the crushing contractor. Aug 8, 2025

Deposit type

  • Epithermal

Summary:

The Mexican Hat property occurs on the eastside of the Dragoon Mountains and is underlain by mixed mafic to felsic peralkaline volcanic rocks. A fault of regional extent bounds the property to the west, and alluvium covers the eastern, northern, and southern extents of the property. A prominent hill, the Mexican Hat Hill dominates, and several smaller hills define the physiography of the property. Several structures of more local extent can be observed on the flanks of the hills on the property and defined by geophysics.

Mineralization
Gold mineralization is associated with moderate to strong oxidized zones of hematite and limonite. Hematite and limonite are directly related to and fill, in part, dominant NE/SW fault and related fractured zones including secondary NW/SE fault and fractured zones. Hematite may be the result of low-temperature alteration of primary or secondary magnetite. Limonite, a secondary mineral after pyrite is common in surface oxidized zones. Malachite and azurite were observed in several locations across the property within trachyte andesite (Webb, 2015). In addition, the main elevated metal assemblage from assay results include Au, Ag, As, Hg and Sb. Limits of mineralized zones have not been determined. No sulphides or visible gold has been identified from surface exploration campaigns.

Alteration
Three main types of alteration are recognized on the Mexican Hat property. First, carbonate alteration is the most common within all Tertiary volcanic rocks mapped on the property. Carbonate alteration is pervasive and ranges from weak to strong. Second, weak propylitic alteration (epidote + weak chlorite in part) was observed and is associated with zones of fracturing accompanied by strong hematization. Third, weak to moderate silicification was observed within and adjacent to some extensional structures. Sericite and K-Feldspar alteration typical of low sulphidation alkali epithermal deposits may be present but these types of alteration were not observed. A Pima or suitable alteration survey may be useful in identifying all alterations present in the main elevated gold/silver zones.

Deposit Type
Porphyry-style mineralization including skarn-type end members containing economically recoverable copper, gold, and sometimes lead, zinc, silver and molybdenum occur in this part of Arizona. The Courtland Gleeson district extends up to and may include the Mexican Hat Property. This mineralization is primarily hosted within Mesozoic sediments and younger intrusions. Placer gold deposits occur in places in washes near the base of the Turquois Mountains.

Younger mineralization hosted in rocks including Tertiary volcanic rocks occur in the area, and at Mexican Hat. The association of alkaline to subalkaline volcanic rocks and the presence of low sulphide concentrations together with the geochemistry of these rocks indicates that the Mexican Hat Property is a low sulphidation epithermal gold deposit.

Reserves at June 22, 2020

Mineral Resources are reported at a 0.20 g/t cut-off grade.
CategoryTonnage CommodityGradeContained Metal
Inferred 36,733,000 t Gold 0.58 g/t 688,000 oz

Mining Methods

  • Truck & Shovel / Loader

Summary:

The PEA considers open-pit mining of the Mexican Hat gold deposit.

The ramps and haul roads assume the use of haul trucks with an operating width of 6.1m. For two-way access, the goal of the road design is to allow a running width of nearly 3.5 times the width of the trucks. MSHA regulations specify that safety berms be maintained at a height of at least ½ of the diameter of the tires of the haul trucks that will travel on roads. The ½ height of the proposed haul trucks' tires is 1.35m. An extra 10% was added to the berm height design to ensure that all berms have sufficient height.

Safety berms assume a slope of 1.5 horizontal to 1.0 vertical. Considering that ramps in the pit only need one berm, the road width of 26m was determined for two-lane traffic, which allows for 3.49 times the operating width of the haul trucks. Single-lane traffic roads are estimated to require 15.5m, which allows 1.77 times the operating width of the proposed haul trucks.

Roads outside of the pit will require two berms, the widths of which are estimated to be 30.5m, which is 3.46 times the width of the proposed haul trucks.

Road designs are intended to have a maximum gradient of 10%, though some may exceed this for short distances around inside turns. Where switchbacks are utilized, the centerline gradient is reduced to about 8%, keeping the inside gradient approximately 12%. Switchback designs have not added the detail for super elevation through the curves, but it is assumed that this will be done when they are constructed.

Pit Design
Each design utilizes 6.0m benches with a catch bench installed every third bench, or 18m. Mexican Hat pits were designed with five phases. Phase 1 mines the larger main portion of the deposit. Phase 2 continues to expand the main portion of the deposit. Phase 3 extends the main pit to the south, and Phase 4 achieves the full depth and extent of the main pit. Phase 5 mines a satellite pit located to the south of the main deposit.

Dump Design
For the PEA, dump designs were created to contain the waste material mined. A 1.3 swell factor was assumed which provides for both swell when mined and compaction when placed into the facility. The backfill will be placed into the South Pit earlier during the project and will be used to regrade the drainage channel to the south.

Mine Production Schedule
Inferred resources inside the pit designs were used to schedule mine production. Monthly periods were used to create the production schedule, with pre-stripping starting in Mexican Hat at month - 6. The start of processing was assigned to month 1, though no gold production was realized until month 2. The total mining rate would ramp up from 5,000 tonnes per day to about 26,500 tonnes per day over a period of 12 months. In later years, when the stripping becomes more significant, a maximum of 46,000 tonnes per day is used.

The PEA has assumed contract mining to simplify the economic study. The contractor will be responsible for supplying equipment to be used for the project.

Personnel Requirements
The mining contractor will be responsible for providing personnel for mining operations. Most personnel will likely be sourced from Tucson or the surrounding area. Thus, there is no need for any camp to house employees. The contractor will be responsible for transportation of employees to and from the site. It is expected that the contractor will have somewhere around 30 crew members per shift and operate two shifts per day. Assuming four shift rotations to provide seven-day per week operations, this would be about 120 employees provided by the contractor.

Additional employees will be provided by the GMV for Mine General Services, which includes mine supervision and engineering and geology services.

Required Heavy Mobile Equipment

Ref. Date: August 8, 2025

SourceSource
HME TypeModelSizeQuantityLeased or
Contractor
Dozer (crawler) Caterpillar D10 1 Leased
Dozer (crawler) Caterpillar D8 1 Leased
Drill 1 Leased
Drill (blasthole) 2 Leased
Grader 16 ft 2 Leased
Loader Caterpillar 992 2 Leased
Loader (mini) 1 Leased
Truck (explosive) 1 Leased
Truck (haul) Caterpillar 777 91 t 8 Leased
Truck (water) 20000 gallons 1 Leased

Comminution

Crushers and Mills

Milling equipment has not been reported.

Summary:

The Mexican Hat project is designed to crush 3.5 million tonnes of resources per annum at a daily rate of 10,000 t/d for 350 days per year.

Run-of-mine material from the pit will be hauled to a two-stage crushing plant operated by a contractor with a nominal capacity of 10,000 t/d of mineralized gold material. The crushed material at 80% passing 38 mm will be conveyed to a stockpile with a 24-hour live capacity. Material will be reclaimed from beneath the stockpile by two feeders (4 ft by 15 ft each) and discharged onto an overland conveyor (1,000 m long by 42 inch wide) leading to grasshopper conveyors at the heap leach pad. Grasshoppers and a radial stacking conveyor will be used for stacking at a rate of 833 t/h over 12 hours per day.

The crushing circuit, designed with 75% availability, achieves a rate of about 1,110 t/h. It reduces run-of-mine material in two stages from a feed size of 1,400 mm to a product at 80% passing 38 mm. The plant will be supplied, operated, and maintained by the contractor.

Lime will be added to the crushed material from a silo on the overland conveyor before stacking onto the heap leach pad.

Processing

  • Smelting
  • Carbon re-activation kiln
  • Crush-and-stack plant
  • Electric furnace
  • Heap leach
  • Carbon in column (CIC)
  • Carbon adsorption-desorption-recovery (ADR)
  • Elution
  • Filter press
  • Solvent Extraction & Electrowinning
  • Cyanide (reagent)

Summary:

Metal Recovery And Operation
For Mexican Hat, the metal recovery from heap leaching will be in an ADR circuit, regeneration, and refinery plant. The plant will have an operation availability of 92% and will be supplied as a vendor package with all the equipment necessary to recover gold from the PLS. Pregnant solution will gravity flow through the heap leach and be collected in a lined pregnant solution pond.

Pregnant solution will be pumped to two trains of 5 CIC in series (total of 10 CIC tanks) where gold in solution is adsorbed onto the carbon. Loaded carbon is advanced in the CIC circuit counter current to the flow of solution. This ensures that the highest-grade gold in solution is in contact with the highest grade loaded carbon and that the lowest grade solution is in contact with the lowest grade carbon to ensure carbon lading efficiency. Loaded carbon is transferred daily from the CIC to the 3 tonne acid wash and elution circuit.

The loaded carbon acid wash is at atmospheric pressure and acid wash solution is circulated to the bottom of the tank and overflows back into the acid wash solution tank at a rate of 2 bed volumes per hour for 1.5 bed volumes. The carbon is then rinsed with water for 30 minutes. After rinsing, the carbon is transferred to the 3 tonne strip vessel where the carbon is stripped under pressure and about 145°C. Strip solution is pumped via the bottom of the strip vessel and flows to the electrowinning circuit where gold is plated onto steel wool. Typically, eleven bed volumes of strip solution are required at a pumping rate of 2 bed volumes per hour.

Stripped carbon will be transferred to the horizontal rotary kiln for regeneration at 750°C. The carbon should be regenerated in the kiln after every desorption stage otherwise carbon loading efficiency will decrease and gold losses in solutions in the CIC will increase.

The gold rich eluate is pumped to the electrowinning cells where a current is passed so that the gold will plate onto the steel wool cathode. The barren solution from electrowinning will recirculate back to the strip solution tank to be used for mixing strip solution. A 20% bleed of barren solution is recommended to avoid buildup of contaminants.

Gold contained sludge from the electrowinning cells will be washed off the cathode and pumped to a plate and frame filter press. Filter cake will be placed in trays into a drying oven. Dried filter cake will be put through mercury retort prior to mixing with smelting flux and put into the electric induction furnace. The slag layer containing impurities will be removed prior to pouring the gold into molds to produce gold doré bars. The doré bars will be cooled, cleaned, sampled, and shipped to market.

Heap Leach Pad Design
The HLF, which includes the HLF, PLS, and event pond is planned to be located north of the proposed pit. The HLF will be constructed in two phases and has been designed for a nominal production rate of 3,500,000 t of mineralized material per year (10,000 tpd) for a total heap capacity of 32.6 Mt assuming a heap bulk density of 1.5 t/m3. The mineralized material will be mined by a standard open pit mining method, crushed to 80% minus 38 mm, and placed through transport and stacking on the HLF in 10-m-high lifts using a conveyor/stacking system. The HLF is anticipated to have a maximum height of 72 m and an overall slope of 2.5H:1V.

The HLF will be constructed in two phases with approximate areas of 192,201 m2 and 373,311 m2 for Phase 1 and 2, respectively (or a total Phase 1 and 2 area of approximately 565,512 m2).

Crushed Material Stacking
The fully stacked HLF (Phase 1 and 2) will have a total capacity of 32.6 Mt of mineralized material stacked in approximately 9.3 years. The Phase 1 will have the capacity to store mineralized material for 2 years, which will constitute the first four lifts to a nominal top surface elevation of approximately 1,444 m. The Phase 2 expansion expands to the west providing capacity to store mineralized material for the LOM, which will constitute seven lifts to a nominal top surface elevation of approximately 1,472 m.

Recoveries & Grades:

CommodityParameterAvg. LOM
Gold Recovery Rate, % 88
Gold Head Grade, g/t 0.55

Water Supply

Summary:

Groundwater has been identified as the best source for a water supply to the Project operations. Successful water wells that are presently shut-in have been drilled (Hernandez, pers. com, 2014) within the general project area. Water has been encountered in every drillhole completed on the Property by GMV, often at depths less than 50 m. Booster pumps would transfer pumped water from the wells to a freshwater tank for distribution to the various site operations. There would be separate fire and potable water tanks.

Commodity Production

CommodityUnitsAvg. AnnualLOM
Gold oz 59,784597,841
All production numbers are expressed as metal in doré.

Operational metrics

Metrics
Daily ore mining rate 10,000 t *
Daily processing capacity 10,000 t *
Annual processing rate 3,500,000 t *
Annual processing capacity 3,500 kt *
Stripping ratio 2.05 *
Waste tonnes, LOM 79,205 kt *
Ore tonnes mined, LOM 38,579 kt *
Total tonnes mined, LOM 117,784 kt *
Tonnes processed, LOM 38,579 kt *
* According to 2025 study.

Production Costs

CommodityUnitsAverage
Cash costs Gold USD 1,319 / oz *  
Total cash costs Gold USD 1,354 / oz *  
All-in sustaining costs (AISC) Gold USD 1,545 / oz *  
Assumed price Gold USD 2,500 / oz *  
* According to 2025 study / presentation.

Project Costs

MetricsUnitsLOM Total
Initial CapEx $M USD 90
Sustaining CapEx $M USD 13
Closure costs $M USD 31,085
Total CapEx $M USD 109.1
OP OpEx $M USD 409.1
Processing OpEx $M USD 339
G&A costs $M USD 40.4
Total OpEx $M USD 788.5
Pre-tax Cash Flow (LOM) $M USD 538
After-tax Cash Flow (LOM) $M USD 378
Pre-tax NPV @ 5% $M USD 390
Pre-tax NPV @ 10% $M USD 288
Pre-tax NPV @ 8% $M USD 325
After-tax NPV @ 5% $M USD 268
After-tax NPV @ 10% $M USD 192
After-tax NPV @ 8% $M USD 220
Pre-tax IRR, % 66.1
After-tax IRR, % 50.2
Pre-tax payback period, years 1.5
After-tax payback period, years 1.8

Personnel

Mine Management

Job TitleNameProfileRef. Date
Consultant - Mining & Costs Tomas L. Dyer LinkedIn Aug 8, 2025
Consultant - Recovery Methods Francisco Barrios LinkedIn Aug 8, 2025
President and CEO Ian Klassen Sep 30, 2025

Workforce

EmployeesContractorsTotal WorkforceYear
83 120 203 2025
80 120 200 2020

Aerial view: