The orogenic deposit model for gold mineralization in the Guerrero Gold Belt (GGB) is considered to be associated with a Pacific Rim style of mineralization as described by Corbett (1998, 2009). GGB mineralization is related to a late Cretaceous to Early Tertiary age skarn porphyry continuum emplaced during a 62 to 66 million year old intrusive event associated with Laramide Compressional Orogeny. Early stage, essentially barren calc-silicate skarn alteration associated with one or more intrusive phases is thought to have developed as a contact metamorphic aureole surrounding hydrated intrusive bodies.

Gold deposition at Ana Paula tends to occur both contemporaneous with and post intrusion, exhibiting at least two mineralizing events. The earliest consists of Au-As-(Bi-Te) disseminated mineralization characterized by progressive mineralization over time through deposition of gold in breccias, stockworks, contact skarn (both endoskarn and exoskarn) and other replacement bodies.

The second mineralization event (Au-Ag-Pb-Zn Hg-Sb) perhaps related to the epithermal style of alteration may be a later hydrothermal phase of the earliest intrusive event (a retrograde overprint?) or may be younger.

The exact timing of gold deposition and the mechanism of deposition within the GGB and at Ana Paula are not yet fully understood and appears to vary among the known deposits, where each deposit shares important characteristics and differences. Intrusions at ........

Open pit mining was selected as the method to examine the development of the Ana Paula Project at this time. This is based on the size of the resource, tenor of the grade, grade distribution and topography.

The deposit will be a conventional, open pit, truck-and-shovel operation. A mill feed of approximately 5,000 t/d is planned over an approximate 8-year mine life. There will be pre-strip material in Year -1, with a full production rampup in year 1.

Pit phase designs were developed for Ana Paula using the three pit optimization shells selected earlier.

Equipment sizing for ramps and working benches is based on the use of 63 t rigid frame trucks. The sizing of the ramp is actually sized for the smaller capacity 56 t rigid frame units, as they are slightly wider than the 63 t rigid frame versions. The operating width used for the truck is 5.7 m. This means that single lane access is 17.8 m (2x operating width plus berm and ditch) and double lane widths are 23.5 m (3x operating width plus berm and ditch). Ramp gradients are 10% in the pit for uphill gradients and 8% downhill on the dump access roads. Working benches were designed for 35 to 40 m minimum on pushbacks.

Ana Paula is designed with three phases. The first phase is a starter phase designed to provide early higher grade material for the plant and minimize strip ratio. The second phase expands on the first targeting the larger portion of the ore body. The final phase requires ........

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