Name: La Arena mine.
Location: The La Arena property is located in the Huamachuco district, Sánchez Carrion province, Department of La Libertad, along the eastern slope of the Western Cordillera of northern Peru.
Controlling Company: Tahoe Resources, through its wholly owned subsidiary, La Arena.
Brief Description: The La Arena mine is a gold oxide openpit, run-of-mine (RoM) heap-leach operation, which has been in production since 2011. The mine currently operates at 36 000 t/d.
The current mine life runs until 2021, although potential exists to develop additional resources below the currently designed pit and extend the mine life, which Tahoe is drill testing.
Brief History: Tahoe acquired the La Arena property in April 2015 as part of its acquisition of Rio Alto Mining. The mine has been in operation since 2011.
Products: Gold.
Geology/Mineralisation: High-sulphidation gold mineralisation at the La Arena mine is hosted in the Lower Cretaceous Chimu formation and is lithologically and structurally controlled, occurring primarily in silicified fractured sandstones and, locally, in hydrothermal breccias. Structural control is mainly associated to the principal north-west to south-east Andean orientation and secondary to tensional fracturing, as well as to bedding planes. Tensional fracturing has acted as a principal fluid channel way, containing oxidised high-sulphidation epithermal gold mineralisation. Fine-grained native gold is free in small proportions as is electrum.
Higher-grade zones of gold mineralisation are directly controlled by the intersection of south-west to north-east faults, which transverse the mineralised trend oriented to the north-west to south-east. The north-west-trending ‘feeder’ structures, locally termed Tilsa structures, have a strike length of about 300 m and thicknesses ranging from a few centimeters to several metres, with grades of 80 g/t to 100 g/t of gold not uncommon. Lower-grade gold mineralisation occurs as thin stockwork and disseminations within the Chimu sandstone.
Reserves: Total proven and probable reserves as at January 1, 2018, were estimated at 44-million tonnes grading 0.4 g/t gold.
Resources: Total measured and indicated resources as at January 1, 2018, were estimated at 49.9-million tonnes grading 0.4 g/t gold. Inferred resources were estimated at 400 000 t grading 0.32 g/t gold.
Mining Method: La Marena is a conventional drill, blast, shovel and truck openpit RoM operation.
Major Infrastructure and Equipment: The La Arena mine includes an openpit, a wasterock storage facility; fully lined leach pads; a lined pregnant solution pond, a lined major events pond (stormwater catchment); an absorption, desorption and refining processing plant;a water treatment plant ;and sundry facilities, including a 600-person camp and associated facilities.
The mining fleet comprises 90 t class rock trucks and 10 m3 hydraulic shovels. Blasthole drilling is performed by diesel-powered rotary single pass track drills. Ancillary support equipment includes motor graders, track dozers and water trucks.
Prospects: Tahoe continues to evaluate the development of La Arena II, a porphyry-hosted copper/gold deposit adjacent to the La Arena mine. A preliminary economic assessment released in February 2018 has shown the potential economic viability of the porphyry-hosted copper/gold deposit worthy of further study.
Contact: VP investor relations Alexandra Barrows
Contact Details:
Tahoe Resources
Tel +1 775 448 5800
Email investors@tahoeresources.com
Website https://www.tahoeresources.com