Name of the Mine
Gualcamayo mine.

Location  
About 270 km north of the provincial capital of San Juan and south-western La Rioja province, west-central Argentina.

Mine Owner/s  
Minas Argentinas SA (MASA), a wholly owned subsidiary of Aisa Group.

Brief Description  
An openpit and underground gold operation. Gold mineralisation occurs in three main areas: Quebrada del Diablo (QDD), Las Vacas, and Salamanca. 

The QDD area includes the QDD Main, Condor, Potenciales, Amelia Inés and Magdalena (together AIM), Target D, QDD Lower, and the deeper carbonate-hosted sulphide deposits Rodado, Santiago and Feeder, which together form the Deep Carbonates Project (DCP). There are also several small satellite deposits.

Brief History  
Gualcamayo reached commercial production in 2009. The mine was on the brink of closure when Aisa acquired 100% of the shares of MASA from Mineros SA in September 2023.

Primary Metals/Minerals  
Gold.

Secondary Metals/Minerals  
Silver occurs in doré and historically contributed 1% to 2% of revenue, but it is not included in mineral resources or reserves.

Geology/Mineralisation  
Gualcamayo comprises sediment-hosted distal-disseminated gold, along with sulphide-bearing skarn deposits and porphyry-style mineralisation. Mineralisation is structurally and stratigraphically controlled across QDD, Las Vacas and Salamanca.

Reserves  
As at June 30, 2021, proven and probable mineral reserves totalled an estimated 3.3-million tonnes at 1.65 g/t gold (combining openpit extensions and underground panels).

Resources  
As at June 30, 2021 (exclusive of reserves) the mine has measured and indicated mineral resources of about 26-million tonnes at 1.93 g/t gold. Inferred mineral resources were estimated at 16-million tonnes at 2.3 g/t gold.

Type of Mine
Openpit and underground mine.

Mining Method  
Openpit ore production uses standard drill-and-blast, and load-and-haul operational procedures. Underground mining is conducted using use sublevel caving and sublevel stoping at Cuerpo Este.

Major Infrastructure/Equipment  
The operation includes primary/secondary/tertiary crushing facilities, an adsorption, desorption, and recovery plant with electrowinning and refinery to doré; heap-leach pads, an accommodation camp, maintenance buildings, and office buildings.

Prospects  
DCP, which consists of the Santiago, Feeder, and Rodado deposits, is the primary target for future expansion. The plan includes the construction of a new underground mine, a milling system, and a floatation plant with a processing capacity of 3 500 t/d to 4 500 t/d. The DCP is expected to yield about 120 000 oz/y of gold for at least 17 years.

Contact Details 
Aisa Group
Tel +1 312 285 8599
info@aisagroup.ca
Website: https://www.aisagroup.ca/