The gold-silver deposits of the Deseado Massif are hosted in silicic volcanic and volcano-sedimentary Jurassic rocks related to arc or back-arc settings in Andean or extra-Andean settings. The ore geology, textures, mineralogy, restricted alteration, and geochemistry of these mineralised occurrences indicate that they belong to the epithermal class of precious metal deposits. The deposits are mainly associated with quartz +/- calcite +/- adularia +/- illite alteration assemblages interpreted to represent low and intermediate sulphidation epithermal type deposits.

At La Paloma, the Sulfuro-Rocio vein system comprises narrow, arcuate, steeply dipping quartz- breccia veins. Drilling has defined four areas of interest:

• The Sulfuro vein, the principal deposit of economic interest, is represented by a single, well developed quartz vein typically 2 m to 4 m in thickness and has a primarily northwest-south southeast orientation with a steep southwestwardly dip. Associated sulphide minerals include pyrite and minor galena and sphalerite.
• The Ramal Sulfuro vein occurs at the northern end of the main Sulfuro vein and is strongly curved from a north-south orientation to east-west and is typically 2 m to 4 m in thickness.
• The Rocio vein occurs to the west of the main Sulfuro vein. The Rocio vein is typically 2 m to 5 m in thickness and dips steeply to the east. It is also arcuate in shape and sub-parallels the Sulfuro vein.
• The Esperanza vein system dips 75 degrees toward Sulfuro and has an average thickness of 0.3 m to 6 m.

A near-surface oxidised resource has been estimated for the Arco Iris vein, located towards the north of the Sulfuro vein system. It is represented by a series of narrow, structurally displaced, sub- parallel aligned, sheared quartz veins hosting erratic precious metal mineralisation.

The La Paloma veins remain open-ended at depth. Geological interpretation of the results of recent geophysical studies strongly suggests that the main Sulfuro vein is additionally open-ended towards the south.

At Martinetas, multiple mineralised structures occurring as “vein swarms” with minor intervening stockwork development occur. Five resource areas have been delineated. The main resource is at the Coyote and Cerro Oro deposits comprising a series of narrow, sub-parallel, anastomosing quartz veins varying in width from tens of centimetres to several metres, and typically averaging 1 m or less in thickness. Au/Ag mineralisation is variable within the veins with some minor stockwork mineralisation extending into the host volcanic lithology. Conceptually, near-surface oxidised stockwork precious metal mineralisation might provide a low grade, conventional, heap- leachable resource.

Other resource areas at Martinetas include the Lucia, Calafate and Armadillo deposits. Precious metal mineralisation associated with these deposits is also hosted by narrow to moderately thick, steep dipping quartz veins of variable tenor.

The MDN operation is currently a producing gold mine. Final construction was completed December 2017 for the 1,000 tpd operation.The mine was “designed” for 1,000 tpd and it has reached 1,200 tpd on occasion.

Commissioning of the operation began in December 2017. MDN began operations of a series of conventional open pit mines with a carbon-in-leach facility. Ramp up continued until late 2019. Currently the operation is mining from three active pits (Coyote, Cerro Oro and Sulfuro) at a rate of +1,000 tpd and the mill is able to handle the throughput. As of the effective date of the technical report, further optimisation is being done to both the mining and milling operation. MDN consists of two fully permitted mining areas, each containing a clustered, shallow pits.

Production began with removal of waste for the construction of the tailings storage facility. Marginal grade was stockpiled at the same time and now a long-term, low-grade stockpile has grown to over 500 kt. It continues to grow as all marginal material is stored here.

Mining is currently split 70% – 30% between the Martinetas pits and the La Paloma pits 60 km away, largely due to the high stripping ratio at La Paloma. The three Pantera drills typically drill out blast patterns on a double bench height of 10 m and a 5 m bench when mining mineralised material. Blast holes are typically 3.5” to 4” in diameter. Waste drilling and pre splitting against the final pit wall is done using 5.5” hole diameters. MDN uses ammonium nitrate/fuel oil (ANFO) explosives with conventional primers and a shock tube ignition system for blasting. The ANFO is charged up by hand. Fragmentation in the muck piles is good and the powder index is 0.5 kg/t.

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The MDN processing facility was designed to process a nominal 350,000 tonnes per annum (tpa),or 972 tpd, of gold-silver bearing material from an open pit operation. The concentrator was designed to produce a gold-silver doré product.

The process flowsheet follows conventional crushing and ball mill grinding and cyclone classification. The gravity concentration circuit in the grinding circuit includes the recovery of coarse and liberated gold using a centrifugal concentrator followed by the tabling of the gravity- gold product to up-grade the concentrate prior to smelting.

The ball mill cyclone overflow is treated in an 8-stage CIL circuit to recover gold from the feed material using activated carbon. Loaded carbon is transferred from the head CIL tank to the elution circuit on a daily basis, while regenerated and/or fresh carbon is brought from the carbon plant for adding to the CIL circuit.

The loaded carbon is initially acid-washed to remove calcium a ........