Name: Antas mine.

Location: Antas is located in the Carajás, 25 km south-east of Parauapebas, in the state of Pará, in the northern region of Brazil.

Controlling Company: Avanco Copper.

Brief Description: Antas is a high-grade openpit copper/gold mine. 

Brief History: The Antas deposit was discovered in 2011 and was  developed under budget in under 12 months. The mine entered commercial production in July 2016 and is already operating above its original design capacity.

Products: Copper and gold.

Geology/Mineralisation: The Antas orebody is located close to the southern border of the Estrela granite complex and is hosted predominantly by mafic metavolcanic rocks, cut by gabbro dykes.

Associated alteration shows a moderate to strong zonation from the surrounding unaltered country rock into the most strongly mineralised portions of the deposit, with hydrothermal alteration zones similar to those recognised at other iron oxide copper/gold (IOCG) deposits in the Carajás. The complex stages of sodic, sodic–calcic, potassic and hydrolytic alteration observed at Antas North are generally similar to the Sossego–Sequeirinho IOCG system in Carajás.

The main orebody is oriented north-east and coincides with the main soil and electromagnetic anomalies. Zones of massive sulphide near the periphery of the ore zones help to generate the high-grade intercepts typically seen in historically reported results.

Most of the mineralisation is concentrated within a steeply dipping body that contains fragments of massive sulphide and disseminated sulphide minerals, within a matrix of hydrothermal breccia.
 

The massive sulphide high-grade zone contains variable proportions of chalcopyrite and pyrrhotite as dominant minerals. Chalcopyrite is the most abundant sulphide, forming a massive aggregate. Sulphide veins are generally not deformed, and planar.
 

The medium-high grade zone also contains variable proportions of chalcopyrite and pyrrhotite, as dominant minerals, and is the most abundant of the mineralised zones. Sulphides frequently form the matrix of hydrothermal breccias.

In the disseminated zone chalcopyrite occurs as fine-medium grained disseminations in the transparent gangue, usually surrounding transparent minerals. Sulphides also occur as fracture fill and small blebs. Commonly, this ore type occurs between narrow medium-high grade and massive sulphide zones.
 

Reserves: Total proven and probable reserves as at December 31, 2016, were estimated at 3.04-million tonnes grading 2.64% copper and 0.58 g/t gold.

Resources: Total resources as at December 31, 2016, were estimated at 5.46-million tonnes, grading 2.43% copper and 0.48 parts per million of gold.

Mining Method: Conventional mining, with load and haul.

Major Infrastructure and Equipment: Mining is undertaken by a fleet of excavators, articulated off-road haul trucks, top hammer drill rigs and auxiliary equipment, including front-end loaders, dozers, graders, water carts and service trucks.

The processing plant comprises a Metso ball mill, Outotec floatation cells and Denver cleaner cells.

Prospects: Based on the current reserves model, the mine will operate until 2021, however, a drilling programme announced in April 2017 is targeting to increase mineral resources and reserves to potentially increase production and extend the life-of-mine.
 

Contact: Head of corporate affairs, Nicholas Bias.

Contact Details:
Avanco Copper
Tel +61 8 9324 1865
Email nbias@avancoresources.com
Website http://avancoresources.com