Name: Aurizona mine.
Location: The Aurizona mine is located in north-east Brazil.
Mine Owner/s: Equinox Gold (previously Trek Mining).
Brief History: The Equinox board approved full-scale construction of the mine in January 2018.
Brief Description: Aurizona is a past-producing, low-cost openpit gold mine with significant infrastructure remaining at site. The mine has average production estimated at 136 000 oz/y.
Primary metals: Gold.
Secondary metals: Not stated.
Geology/Mineralisation: The Aurizona mine is hosted by the Aurizona Group and the Tromai Intrusive Suite along east-north-east-trending shear zones – the Piaba and Boa Esperança deposits are two shear-hosted gold deposits.
The Piaba deposit is a tabular auriferous zone (10 m to 50 m) with a 3.3 km extent. The Piaba deposit is hosted within the metavolcano-sedimentary rocks of the Aurizona Group. The entire package is cut by north or north-north-west-trending andesitic dikes. The deposit trends east-north-east and dips steeply (80°) north-north-west.
Piaba is hosted in quartz-diorite rocks with diorite in the hanging wall and chemical-carbonaceous metavolcano-sedimentary rocks in the footwall. The deposit displays intense weathering alteration with an average depth of oxidation at 60 m. The Piaba deposit is intensely hydrothermally altered by silica, sulphides sericite, chlorite, carbonate and epidote. The alteration often masks the original protoliths.
The Boa Esperança deposit is hosted by diorite within a metavolcano-sedimentary sequence. The diorite is associated with lenses of gabbro and andesite, which are in nonconformable contact with the metavolcano-sedimentary sequence. The metavolcano-sedimentary sequence includes carbonaceous metagraywacke, carbonaceous metachert and carbonaceous phyllites. It is postulated that the metavolcano-sedimentary sequence was intruded by the mafic units. This is supported by the occurrence of assimilation of fragments of the metavolcano-sedimentary rocks within the igneous rocks.
Reserves: Total proven and probable reserves as at December 31, 2018, were estimated at 19.84-million tonnes grading 1.52 g/t gold.
Resources: Total measured and indicated resources as at December 31, 2018, were estimated at 12.8-million tonnes grading 1.68 g/t gold. Inferred resources were estimated at 17-million tonnes grading 1.98 g/t gold.
Mining Method: Openpit.
Major Infrastructure and Equipment: The project includes an 8 000 t/d processing plant.
Prospects: Exploration at Aurizona has identified a structurally controlled mineralized corridor that extends another 5 km along strike to the west of the existing reserve pit, smaller satellite deposits to the north-east of the reserve pit, and a substantial underground resource, demonstrating potential to significantly extend the Aurizona mine life
Contact Details:
Equinox Gold
Tel +1 604 558 0560
Email ir@equinoxgold.com
Website https://www.equinoxgold.com