Each of the Rovina, Colnic, and Ciresata porphyries share many basic geologic-mineralization attributes. These include association with both subvolcanic intrusives of similar composition and similar alteration suites. The mineralized porphyries at Rovina, Colnic, and Ciresata display moderate to intense potassic hydrothermal altered cores, and strong quartz stockwork veining. The Au-Cu mineralization manifests as stockwork veining and disseminations of pyrite and chalcopyrite, centred on porphyritic, subvolcanic-intrusive complexes of hornblende-plagioclase diorites. The Colnic and Ciresata porphyries classify as gold-rich, with the Rovina porphyry falling within the Cu-Au subtype. All three porphyries contain many of the features common in gold-rich porphyries[i.e. dioritic, calc-alkaline stock associated and abundant magnetite alteration (Sillitoe, 2000)].

Geometry of the mineralization and host porphyries is different for each of the deposits. At Rovina, the host porphyries are generally cylindrical and vertical. At Colnic, the porphyries are lobate, with mineralization decreasing with depth and a phyllic-altered cap locally preserved. Both Rovina and Colnic porphyries intrude extensive igneous- magmatic breccia carapaces, whereas Ciresata mineralization is centred on a relatively narrow subvolcanic “neck” with a significant amount of mineralization hosted in adjacent hornfelsed sediments.

Copper-gold mineralization at Rovina is hosted in multiple composite plagioclase-hornblende porphyritic subvolcanic intrusives. This mineralization reaches the surface and is exposed in one location as outcrops in the Baroc valley drainage over approximately 300 m. The remaining sparse and scattered outcrops are phyllic-altered fragmental volcanics and porphyritic volcanics, which comprise a mapped phyllic alteration halo of 1,000 x 600 m. The mineralized porphyries are cylindrical and vertical, with mineralization extending up to 600 m below surface. At least three mineralized porphyries are recognized. The main porphyry (Rovina Porphyry) intrudes (or is surrounded by) a brecciated porphyritic unit. This breccia unit is locally mineralized and is interpreted as an intrusive magmatic breccia (IMB) carapace to an upper-level intrusive. The last, post-mineral stage of intrusive activity is the emplacement of a phreatomagmatic breccia complex, which cuts earlier porphyry units and is grade destructive.

Gold-copper mineralization is associated with pyrite-chalcopyrite-magnetite occurring in veinlet stockworks and as finely disseminated grains. Oxidation is restricted to the uppermost few metres, with the exception of a small area in Baroc Valley at the Rovina porphyry where weathering oxidation is 15 to 25 m deep within the copper-gold mineralization. In this area, secondary copper minerals malachite and chrysocolla are observed in the weathering zone, and minor occurrences of supergene copper minerals (chalcocite) occur below the weathering zone, typically associated with short drill hole intervals of elevated copper grades.

Deposit-scale controls to mineralization are the localization of the principal hornblende-plagioclase porphyry intrusion (Rovina Porphyry PoC), which is elongated in a northwesterly direction, measuring approximately 600 m northwest x 350 m northeast. This porphyry has vertical contacts over at least 600 m in depth, and apparently terminates northward in the northeast-trending Baroc Valley zone. Lower-grade copper-gold mineralization extends down the Baroc Valley zone to the southwest, to include the Baroc Valley porphyry as a satellite to the main Rovina porphyry. This intrusive geometry suggests possible northwest structural control for emplacement of the Rovina Porphyry intersecting a northeast structural zone controlling emplacement of the Baroc Valley Porphyry.

At Rovina, two early-stage magmatic-fluid alteration events are recognised (PT, MACE, and a locally occurring magnetite-only alteration). Higher grades of gold-copper mineralisation are best developed and associated with broad zones of intense quartz-sulphide stockwork veining (up to 70 % of rock mass). Stockwork veining intensity typically correlates with alteration intensity, and in higher-grade zones, such as in the Baroc Valley area, intense stockwork veining with overprinting MACE alteration obscures all primary rock textures. The earliest copper-bearing assemblage is observed in both early magnetite-bearing veinlets/stringers and disseminated in the rock mass and consists of magnetite + chalcopyrite + bornite + minor pyrite. Cross-cutting veinlets indicated multiple fracturing and hydrothermal pulses. Seventeen vein types have been recognised, with five types most common with gold-copper mineralisation. These five vein types are hairline magnetite stringers, quartz veins, quartz-magnetite-sulphide veins, quartz-sulphide veins, and banded quartz-sulphide veins.

Gold-copper mineralization at Colnic is hosted in multiple composite plagioclase-hornblende porphyritic subvolcanic intrusives. This mineralization reaches the surface in the Rovina Valley and is exposed in outcrops and road-cuts in the valley bottom over a distance of approximately 400 m. The remaining sparse and scattered outcrops are phyllic-altered porphyritic volcanics and Cretaceous sediments, and propylitic-altered hornblende andesites. The Colnic deposit has a large phyllic alteration halo covering 2,000 x 1,700 m. Two mineralized porphyry-centres comprise the bulk of the Colnic deposit; one occurring in the Rovina Valley (Colnic Porphyry) which partially outcrops, and a second centred approximately 200 m southeast on F-2 Hill (F-2 Hill Porphyry).

Gold-copper mineralization is associated with pyrite-chalcopyrite-magnetite occurring in veinlet stockworks and as disseminated grains.

Deposit-scale controls to mineralization consist of the localization of two hornblende-plagioclase porphyry centres; the Colnic porphyry and the F-2 Hill porphyry. The Colnic porphyry occurs in the Rovina Valley, elongated parallel to the northeast-trending valley over an area approximately 400 m long x 200 m wide. This is interpreted as the older porphyry, and its upper part contains the highest grades at Colnic. The centre of the F-2 Hill porphyry complex occurs approximately 150 m southeast of the Colnic porphyry. Interpreted structural controls on the emplacement of these porphyries are the northeast- trending Rovina Valley (as suggested by an inter- mineral dike and breccia swarm in the upper part of the Colnic porphyry) and the northwest-striking Chubby’s Fault/fracture zone (a brittle, post- mineral structure; however, maybe a re-activated older structure, as evidenced by a spatial mineralization association at depth).

Ciresata contains the highest average gold grades in the RVP, with gold-copper mineralization hosted sub-equally in a Neogene subvolcanic ”neck” and adjacent hornfelsed Cretaceous sediments. The subvolcanic intrusion is a relatively coarse- grained hornblende-plagioclase porphyry (Early Mineral Porphyry), with a narrow vertical feeder zone and ”ballooning” at the dipping planar contact between the hornfelsed Cretaceous sediments and an older subvolcanic intrusion (Host Rock Porphyry), approximately 250 m below the present surface.

Gold-copper mineralisation at Ciresata is associated with magnetite-pyrite-chalcopyrite occurring in veinlet stockworks and as finely disseminated grains over a wide area of approximately 450 m (NW-SE) by 300 m (NE-SW) and narrowing with depth. Recent deep drilling has intersected mineralisation 500 m below previous drilling, suggesting approximately 1,000 vertical metres of mineralisation. This mineralisation is centred on the early mineral porphyry (EM-P), with approximately 65 % hosted in the hornfels sediments (SED) and 35 % in the EM-P. In general, grade decreases as a function of distance away from the EM-P-to-SED contact.

All deposits will be mined utilising conventional truck and shovel methods to supply ore to the ROM tip and waste to the respective pit’s waste crushing and conveying station, which will transport the waste to the Colnic stockpile area and backfill the Colnic pit.

A LOM schedule has been developed to supply one processing plant for the full LOM. The processing plant has a planned throughput of 7.2 Mt/a (Colnic pit and then Rovina pit) and a LOM of 16 years, excluding the Colnic low-grade stockpile. The LOM schedule considers the in-pit and stockpile blending requirements during the life of each pit, as well as the changeover from Colnic to Rovina ore supply to the processing plant.

The Owner’s mining fleet will be responsible for all mining-related earthmoving activities.

Most of the ore and waste materials will be drilled and blasted as there is a nominal amount of free dig/oxidised materials.

Free-dig and blasted waste will be loaded with 200 t class hydraulic backhoe excavators, hauled with 90 t haul trucks, and stockpiled at designated waste stockpile locations, which will be systematically dozed and levelled to allow the stockpiles to be raised in accordance with the design parameters.

Free-dig and blasted ore will be loaded with 200 t class hydraulic backhoe excavators and hauled with 90 t haul trucks to the plant feed ROM pad. There the ore will either be direct tipped into the crushing facility or placed on the ROM pad stockpile areas, depending on the grade control strategy being applied.

The project is to be mined utilising proven drilling, blasting and earthmoving equipment operated by an experienced Owner’s team and well trained workforce.

Owing to the significantly higher elevation and limited capacity of the Colnic waste storage facility, a waste-only crushing and conveying system will be installed for waste transportation only during the operational life of the Colnic pit. This crushing and conveying system will be reclaimed at the end of the Colnic pit’s life and reused for both waste and ore batched transportation to the Colnic backfill site and the Colnic ROM pad position from Year 9 till the end of the Rovina pit life.

The Colnic pit will commence production first as it has the best incremental value per tonne and as such will assist in delivering higher mill feed grades early in the project life.

Approximately six to seven months of waste stripping will be required to expose sufficient ore to maintain a constant ore feed of 7.2 Mt/a post commissioning and the planned process plant feed build-up.

The mining of the two deposits runs for a period of approximately 16 years based on the current production schedule and design parameters.

The peak production requirements of the total mining fleets have been capped at an estimated 27.4 Mt/a (total material movement).

ROM ore is crushed in a single-stage crushing circuit utilising a gyratory crusher. The crushed ore is conveyed to a stockpile and is then withdrawn using pan feeders onto the mill feed conveyor.

The milling circuit consists of a primary SAG mill and a secondary ball mill. A pebble crushing facility utilises a cone crusher to crush pebbles from the SAG mill discharge screen, and the crushed pebble material is recycled back onto the mill feed conveyor.

Crushing and Stockpiling
Ore is delivered via haul trucks into the ROM receiving bin, which feeds directly to the primary crusher. The crusher product reports to the product bin. The primary crusher discharge apron feeder transports the crushed ore to the crusher sacrificial conveyor, which transports the crushed ore to the overland conveyor.

A belt weightometer installed on the sacrificial conveyor records the feed rate from the gyratory crusher. While on the sacrificial conveyor, the ore travels under a tramp metal magnet so that any metal present can be removed. A metal detector is situated further along to detect any metal that was not successfully removed from the crushed ore. If metal is detected, the sacrificial conveyor will stop.

The overland conveyor conveys the crushed ore onto the tripper conveyor, which discharges to the crushed ore stockpile. The crushed ore stockpile provides a surge capacity and ensures a constant feed to the milling circuit when maintenance work is being carried out under scheduled shutdown or upset conditions in the crushing section.

Dust control is very important in the crushing and mill feed storage sections. Dust control is by way of both containment and suppression. The dust suppression system uses fine water sprays at the main dust-generating points in the crushing, stockpile and mill feed sections.

Stockpile Reclaim and Milling
The mill feed stockpile is fitted with six vibrating feeders. The feeders are equipped with variable-speed drives for better mill feed control. The feeders regulate the rate of ore withdrawal from the stockpile and, consequently, the SAG mill feed rate. The feeders withdraw material from the stockpile onto the mill feed conveyor, which conveys the material to the SAG mill.

The milling circuit is an SABC configuration, consisting of a SAG mill, ball mill and pebble crushing circuit. The SAG mill is equipped with a variable-speed drive, which allows the mill to treat ores with varying work indices by changing the mill energy input and protects the mill shell liners in the event of low-load conditions. The SAG mill slurry discharges through a trommel screen, and the screen oversize is conveyed to the pebble crushing circuit for further size reduction, from where it is directed onto the mill feed conveyor.

Overband magnets on the pebble crusher feed conveyors pick up any steel balls discharged together with the pebbles. A metal detector on the pebble conveyor detects any metal not successfully removed by the tramp metal magnet. A bypass system is incorporated in the design before the pebble crusher feed bin to bypass the pebble crusher and divert the material to the SAG mill conveyor when the pebble crusher is not available due to maintenance.

The SAG mill discharg e trommel screen undersize is combined with the ball mill discharge in a common sump and then pumped to a hydrocyclone cluster for classification. The hydrocyclone overflow advances to the flotation circuit via the trash screen, and the hydrocyclone underflow gravitates to feed the ball mill. A trommel screen is installed at the discharge end of the ball mill for the removal of scats. The scats are collected in the scats bunker periodically using a front-end loader (FEL).

Process water is fed at a ratio to the SAG mill feed tonnage to obtain the required mill discharge density and is also added at a controlled rate to the mill discharge sump to adjust the set cyclone feed density. The balance of the process water to the circuit is used for ball mill dilution and high-pressure spray water on the mill discharge screens to ensure efficient wet screening.

Milling and cyclone spillage is contained by a concrete bund area with a sloped-end floor to direct spillage to the mill feed and mill discharge end spillage sumps. Each sump has a vertical spindle pump that pumps the spillage to the mill discharge sump.

The process plant will consist of a gyratory primary crushing circuit, a semi-autogenous grinding (SAG) mill in conjunction with a ball mill and pebble crushing (SABC) circuit, and conventional froth flotation as a mineral separation technique to beneficiate the sulphide copper ore.

The discharge from both mills gravitates to the common sump and is pumped to a cyclone cluster. The cyclone underflow slurry gravitates to the secondary ball mill. The cyclone overflow slurry gravitates onto the trash removal screen, and the screen underflow gravitates to the flotation feed surge tank. The rougher scalper concentrate reports to the concentrate thickener, and the rougher-scavenger concentrate is transferred to the regrind mill for further liberation of gold and copper.

After regrinding, the concentrate is transferred to a multistage cleaner flotation circuit. The final concentrate from the last cleaner stage and rougher scalper is thickened, filtered, and bagged for sal ........