Deposit Types
Rozino is a LSE gold deposit hosted within breccia and conglomerate Palaeogene sediments as disseminations, replacement and vein mineralization. The dominant mineralization strike is northwest, parallel to the regional extensional fault regime, with local mineralization development controlled by the intersection of steep structures sub-parallel to the bounding extensional faults, and gently dipping bedding.

Velocity’s exploration focussed on the dominant northwest trend of veins within the Palaeogene sediments. The veins appear to be controlled by steep structures interpreted to extend into the basement.

Drilling to date has not intersected significant gold mineralization within the basement. However, drilling has intersected crustiform gold and base-metal bearing, northwest striking LSE veins within the basement. These veins are generally narrow and rarely wider than 10 centimetres. The LSE hydrothermal fluids were confined within the impermeable basement and these non-reactive fluid pathways have very narrow alteration selvedges that are difficult to detect by drilling.

Upon reaching the basal unconformity the hydrothermal fluids would have de-pressurized and throttled boiling is the interpreted mechanism for gold deposition. The poorly consolidated breccia conglomerate sediments are interpreted to have been wet, further neutralizing the hydrothermal fluid, creating disseminated gold haloes peripheral to the boiling zones. Where hydrothermal pathways intersect coarse sandstones, stockwork quartz carbonate veins are developed at the expense of disseminated mineralization.

Velocity consider that all untested parts of the Palaeogene basins in the Tintyava Property have the potential to host epigenetic, LSE mineralization analogous to that at Rozino, making the basin sediments to the south of Rozino targets for further exploration.

Velocity’s exploration of Tintyava Property has included soil sampling of areas within the BRSZ where similar rocks to those hosting the Rozino deposit outcrop,including the Rozino South and Kazak areas. For large areas of the Property, the prospective rock units are overlain by younger sedimentary rocks, recent alluvial cover or both. Velocity considers that for such areas, any potential mineralization is likely to be geochemically blind to soil sampling, and that deeper drilling is an appropriate exploration approach.

Velocity have identified telethermal alteration at Tashlaka, characterized by hot springs silicification and associated pathfinder geochemistry including arsenic, antimony, barium, mercury and silver. Although no significant gold grades have been noted in this area, the identified alteration aids geological understanding of the Property, and exploration target. This alteration is interpreted to indicate that despite lying at a lower topographic level than the Rozino deposit, the alteration represents higher levels of the hydrothermal system. This is indicative of as yet undefined post mineralization extensional faulting between Tashlaka and the Rozino Deposit.

Mineralization
The following summaries of the Rozino mineralization is derived from Hogg (2017) and notes supplied by Velocity.

Rozino is a low sulphidation epithermal gold deposit hosted within generally brecciated and conglomeratic Palaeogene sedimentary rocks as disseminations, replacement and vein mineralization. The mineralogy consists mainly of pyrite with traces of base metals and rare arsenopyrite. Gold is present at sulphide mineral boundaries and to a lesser degree as free grains or encapsulated inclusions. Gangue minerals consist of silica, iron carbonates and adularia. Alteration is characterized by a quartz, carbonate, chlorite, adularia, pyrite assemblages.

The dominant mineralizationtrend is northwest and parallel to the regional extensional fault regime with local mineralization development controlled by the intersection of steep structures sub-parallel to the bounding extensional faults, and gently dipping bedding. Mineralization is interpreted to have been emplaced around 100 to 150 metres below the palaeotopographic surface and related to shallow extensional faults representing reactivation of pre-existing steep structures.

Rozino mineralization controls include olistostrome bodies of metamorphic basement that effect the distribution of mineralization within the sedimentary basin Brecciated boundaries of the olistostrome bodies are generally more strongly mineralized than their massive cores which are generally poorly mineralized.

Drilling has intersected mineralization over an area about 800 metres by 1,000 metres to a vertical depth of around 195 metres. The mineralization is interpreted to be completely oxidized to average depth of about 11 metres, with fresh rock occurring at an average depth of about 22 metres.

The Rozino Gold Project comprises a single open pit utilizing standard mining equipment to selectively extract the ore over a nine year period (inclusive of a two year pre-stripping period). The pit will be mined in two phases utilizing a waste rock dumping and backfill strategy that provides a compact footprint. The mining is at extraction rates of up to 22,000 tpd using 90 tonne class excavators and 55 tonne capacity haul trucks. All material will require blasting. The schedule delivers higher grade ore directly to the plant in the initial five year period of the mine life at 5,000 tpd. Low-grade ore is stockpiled during this period and reclaimed for processing when the pit is exhausted. The resulting tailings from the low-grade ore are stored in the pit.

The mine plan has a pre-stripping period that is carefully balanced to produce waste rock for the construction of the water storage dam walls, the TMF embankment and ore stockpile pads. The pre-stripping period also delivers a small amount of ore that will enable the plant commissioning and start-up. Although the pre-stripping is over a two-year period, the first year entails mostly road building, clearing, grubbing and topsoil removal.

Mining will be by conventional open pit drill and blast followed by load and haul. The mining cycle commences with a grade control process that will utilizereverse circulation (RC) drilling on a 5 x 8 m pattern over 16 m of depth. The results of the grade control evaluation will be used to define ore block geometries leading to ore / waste definition, appropriate blasting patterns and mine sequencing. Drilling and blasting will be performed on 5m benches. The ore and waste, although blasted on 5 m benches, will be extracted on 2.5 m flitches. The equipment selected is of a type that will enable selective mining of the ore. For this, the ore bucket of the excavator is half the width of the SMU and the truck sizeallows for three full truck-loads per SMU. The excavator and truck type are matched for swing reach, height, and optimal passes per truck load.

The sequencing of grade control, blasting, water control and excavation will require expert planning and operations co-ordination. It will be imperative that the mining team are focussed to grade delivery to the plant whilst maintaining all other mining metrics.

The compact nature of the operation means that an automated truck dispatch system will not be required. Management of hauling from source to destination will be via a centralized control room equipped with computer equipment, telephone network and CB Radio TX/RX system.

The crushing circuit is designed to produce a crushed ore of P8012mm.

The crushing circuit consists of three crushing stages; a primary jaw crusher, followed by secondary and tertiary cone crushers. ROM ore is either direct-tipped from the pit or fed via a Cat 966 loader from the stockpile to a 100t wear plate lined coarse ore bin. A 700mm x 700mm screen will prevent oversize entering to the jaw crusher. A fixed mounted 15kW hydraulic hammer will break oversizeore. The ROM bin apron feeder (1300 mm x 6400 mm 22kW) will supply the primary jaw crusher (42” x 48” 160 kW). The crushed rock reports to the screen via a 32” X 45m conveyor. A magnet will remove steel scrap to a metal scrap bin. Separate dust collectors will aid water sprays for dust suppression and maintain air quality within each of the crusher buildings. A 5t hoist is provided to aid maintenance in the primary crusher building.

Primary crushed material is screened using a double-deck 8’ x 24’ 45kW screen; the undersize reports to the fine-ore stockpile and the screen oversize products report to the secondary cone crusher and tertiary cone crushers respectively. The secondary and tertiary crushers operate in a closed loop with the double-deck screen until all material is fed to the fine-ore stockpile via the lower deck of the sizing screen. Two belt weightometers are provided. Both cone crushers include lube and cooling units. The secondary crusher is a Metso Nordberg HP600 315kW unit,and the tertiary is a HP800 500kW unit.

Assuming a 16-hour operation and an average equipment availability of 75%,a 5,000 tpd throughput is may be achievedby the installation of HP600 and HP800 for secondary and tertiary cone crusher duties respectively.

A conventional three-stage crushing circuit followed by a ball mill was selected as the preferred grinding circuit for the Rozino plant. This arrangement demonstrated lower capital and operating costs compared to the alternative primary crushing than a SAG-Ball comminution circuit evaluated.

The grinding area consists of a ball mill operating in a closed circuit with a cyclone classification cluster. The grinding circuit is designed to produce a P80 75 µm.

The ball mill dimensions are 4.88 m diameter x 7.62 m length (16’ diameter x 25’ length) mill with a 3,500 kW motor. The ball mill installation includes trunnion and gear box lubrication, cooler systems and control system. The ball mill discharges into a pump-box which feeds the cyclone pack via a cyclone feed pump, in a duty/standby arrangement. The cyclone pack consists of 14 cyclones, of which only 12 are operational at any time. The cyclone overflow gravitates to the flotation area, whilst the underflow is re-circulated back to the head of the ball mill.

The Rozino plant consists of the following process unit stages:
• Crushing, sizing and conveying
• Fine ore storage (covered stockpile)
• Grinding (ball mill)
• Flotation
• Tailings thickening
• Concentrate thickening and filtration
• Tailings disposal
• Services: water, air, and reagent systems

Flotation
Conventional tank cells were selected for the flotation circuit. Conventional tanks are more cost effective than staged flotation reactors (SFRs) from the perspective of capital and operating cost.

The sizing and selection of flotation cells were based upon laboratory float times, an industry scale-up factor of 2.5, and an assumed froth factor of 0.85.

Four rougher cells will be installed to prevent ‘short circuiting’

The flotation circuit consists of two conditioning tanks with agitators, four rougher flotation cells, two scavenger cells and two cleaner flotation cells.

The cyclone ov ........