On 5 October 2021, Navarre entered into a binding asset sale agreement (Asset Sale Agreement) under which Navarre, via its 100% owned subsidiary Navarre Minerals Queensland Pty Ltd (Navarre Minerals Queensland), acquired Mt Carlton and the Crush Creek project (Crush Creek), located in Queensland, Australia (collectively, the Mt Carlton Operation).
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Summary:
Mt Carlton Gold Mine and Crush Creek project, located in Queensland, Australia, collectively, the Mt Carlton Operations.
Mt Carlton
The Mt Carlton Mineral Resource includes the V2 open pit and underground mines, the A39 underground mine, Telstra Hill, the Tailings Storage Facility (TSF), surface stockpiles and the satellite deposit of Mt Carlton United.
The Mt Carlton deposits are hosted within Early Permian Lizzie Creek Volcanic Group rocks close to the northern margin of the Bowen Basin. Mineralisation at Mt Carlton ranges from intermediate to high sulphidation epithermal gold-silver-copper mineralisation. V2 and A39 are high sulphidation epithermal gold-silver-copper rich deposits hosted within a doubly plunging rhyodacite package, with the higher-grade mineralisation occurring in steeply dipping NE trending structures surrounded by lower grade flat to shallowly dipping stratiform mineralisation. Mt Carlton United and Telstra Hill are intermediate sulphidation epithermal gold-silver-copper deposits, hosted within rhyodacite volcanic and volcaniclastic sequence.
V2 is a high-sulphidation epithermal gold-silver-copper rich deposit hosted within a rhyodacite package, with the higher-grade mineralisation occurring in steeply dipping NE-trending structures surrounded by lower grade flat to shallowly dipping stratiform mineralisation.
The gold mineralisation at V2 is orientated in a predominantly NE-SW trend with strike extents of 750 metres, across strike extents of 700 metres and dip extents of 250 metres. The NE trending, high-grade feeder structures vary in width from 1 to 20 metres with the thicker parts often associated with the thickest part of the shallow dipping low-grade halo zone toward the upper contact of the rhyodacite. The copper and silver mineralisation extends 750 metres along and across strike with a dip extent of 250 metres, although the mineralisation does thin quite considerably along strike to the NE. Copper mineralisation is significantly more extensive than both gold and silver particularly in the upper part of the deposit leading into the upper contact of the rhyodacite.
Mt Carlton United (MCU) is considered to be an intermediate sulphidation epithermal gold-silver-copper dominant deposit, hosted within the same rhyodacite volcanic and volcaniclastic sequence that hosts the V2, Telstra Hill and A39 deposits. MCU comprises two distinct mineralised zones, Far West (FW) and EastCentral-West (ECW) separated and offset by a post-mineralisation, NW striking fault.
The ECW component represents an up-faulted block within the gold-copper-silver rich part of a medium to high sulphidation epithermal system. Mineralisation is predominantly structurally controlled and is hosted within a series of sub-parallel, stacked, moderately dipping, E-W striking structures high-grade mineralised veins/breccias surrounded by a halo or stockwork of lower grade mineralisation developed within the upper rhyodacite. The silver mineralisation is closely correlated with the gold mineralisation. A small N-S striking post-mineralisation fault has been identified causing a slight offset in the mineralisation between the central and western parts of the ECW. ECW mineralisation extends 600 m E-W along strike with the stacked lenses covering approximately 100 m N-S. The mineralisation has been defined between 75 – 100 m down-dip to a depth of 55 – 75 m below surface. Individual high-grade lenses of gold, silver and copper vary between 1 – 5 m in width, surrounded by a lower grade halo up to 30 m thick.
FW mineralisation extends 600 m E-W along strike, with the stacked set of mineralised veins covering over 200 m of N-S lateral extent. The dip extents of several lenses extend up to 150 down-dip to approximately 110 m below surface although these lenses remain open at depth. Gold mineralisation widths vary between 0.5 m and 5 m wide for the high-grade lenses surrounded by a lower grade halo between 10 – 30 m thick. The silver mineralisation is generally thicker with widths between 25 – 50 m over the same lateral extents as the gold.
Telstra Hill is an intermediate sulphidation epithermal gold dominant deposit, hosted within the same rhyodacite volcanic and volcaniclastic sequence that hosts V2 and Mt Carlton United. The gold mineralisation at Telstra Hill has been defined over 380 m E-W with N-S extents ranging from 150 – 250 m. The shallowly-dipping, higher-grade stacked lenses vary from 1 to 5 m thick, with lateral extents ranging from 100 to 200 m (E-W) and strike extents in the vicinity of 50 – 100 m. The silver and copper mineralisation have been modelled between 10 – 30 m thick as shallowly dipping zones with extents up to 500 m E-W and 300 m N-S.
The primary control on Telstra Hill gold mineralisation is stratigraphy, with a set of shallowly dipping mineralised lenses hosted within and oriented sub-parallel to the upper part of the host rhyodacite package. The underlying lower rhyodacite is unmineralised. The rhyodacite package is cross-cut and offset by two normal faults, the first being a steeply S-dipping, ENE striking fault with an interpreted south block down sense of movement. A second, NNW striking, steeply E-dipping normal fault crosscuts the stratigraphy, offsetting the rhyodacite package with an east-block down sense of movement. These two faults are interpreted to be syn to post the mineralisation as high grade mineralisation is associated with these structures.
Crush Creek
Crush Creek mineralisation is located within the apex of Bowen Basin volcanic stratigraphy which comprises the late Carboniferous to early Permian Lizzie Creek Volcanics, consisting locally of andesitic and felsic derived volcaniclastics, sub-volcanics and lavas, including a series of rhyolitic intrusives and extrusive flowdomes. The low sulphidation epithermal gold-silver mineralisation at BV1 is structurally controlled within steep to sub-vertical N-S striking structures hosted in andesitic lavas and volcaniclastic rocks. Mineralisation is associated with quartz vein and silica breccia development within these structures.