R3D Resources (ASX:R3D) reports it has encountered ‘encouraging’ zinc intersections at the Queen Grade Zinc Project, located in the Chillagoe region of Far North Queensland.
Drillhole TDH24 returned 12m @ 10.7% Zn, 7.5g/t Ag and 0.15% Cu including 1m @ 25.5% Zn 30m below historical drilling.
In July, the company reported the same hole had intersected around 6m of massive sulphide dominated by sphalerite (zinc sulphide) followed by a further 6m of semi-massive and banded sulphides from 160.7m to 172.6m, with the true width estimated at 9m.
R3D reports the Queen Grade zinc skarn mineralisation outcrops on a ridge west of the copper mineralisation and is within the Tartana mining leases.
In July, the company commenced a drilling program to test the depth extensions to the zinc skarn mineralisation defined by historic drilling, and this mineralisation reportedly has similarities to the King Vol zinc mineralisation which is 800m further west and owned by Aurora Metals (ASX:1AE).
The company also notes the mineralisation is widening and continuing at depth.
R3D says further drilling is pending assays and it will develop an orebody model with detailed plans and sections when it has received the assays associated with the Queen Grade drilling.
R3D also reports it has started a 1,340m reverse circulation (RC) campaign at the Tartana Copper and Zinc Project aiming to drill the northern oxide copper zone to establish additional heap leach resources, and deeper drilling of the copper mineralisation in the open pit to extend the recently announced copper resource to a 100m depth.
The company says oxide copper mineralisation has been intersected in historical drilling north of the existing open pit and potentially represents mineralisation that may be leached for future copper sulphate production.
Recent leach testwork on the open pit resource announced in September has indicated low leaching recoveries, and that the ore predominantly comprises primary (chalcopyrite) mineralisation.
With this development, the company has decided to conduct drilling which will extend this resource to approximately 100m depth and review the cut-off grade in line with copper grades associated with conventional sulphide processing.
It also notes samples of the mineralisation have also been sent to Tomra for testing with ore sorting techniques.
R3D Managing Director Stephen Bartop said the drilling program is likely to expand the company’s copper resources.
“As exploration advances, the opportunities on the Tartana mining leases are increasing, particularly in relation to primary zinc and copper mineralisation and the current drilling program is likely to expand our copper resources”
“As exploration advances, the opportunities on the Tartana mining leases are increasing, particularly in relation to primary zinc and copper mineralisation and the current drilling program is likely to expand our copper resources.
Meanwhile staged commissioning plans are being developed for the copper sulphate plant with key items on order, being repaired or installed including the dryer which is being installed next week.”
At the Tartana open pit, the company recently reported an indicated and inferred resource totalling 1.9Mt @ 0.56% Cu for 10.625 tonnes of copper at a 0.2% Cu cut-off grade.
Details of this resource were reported in September, and the resource was based on the supergene zone immediately in the base of the pit and to a depth ranging from 10m to 40m based on observed secondary sulphides.
It says follow-up leach testwork has indicated that the mineralisation is largely primary (chalcopyrite) mineralisation and therefore is more amenable to conventional sulphide processing.
The resource estimation reported in September included intersections from the historical pit floor such as 9m @ 1.55% Cu and 7m @ 1.07% Cu in TRCH73, 14m @ 1.01% Cu in TRCH72 and 39m @ 0.77% Cu from TRCH63.
In view of the mineralisation style and the encouraging intersections, R3D has proposed a 3 hole drilling program which will allow for the estimation of an inferred resource to a depth of around 100m.
The drilling leverages off the historical drilling including 68 holes which have been verified during the recent drilling program.
In addition, the company says historical drilling has often only assayed for copper and there may be potential for silver and other metal credits which will be tested in the current drilling program.
Separately, R3D has dispatched samples to Tomra for testing and ore sorting, and the company has been advised that the ore may be amenable to ore sorting as the chalcopyrite-pyrite mineralisation occurs on stockwork veins and bedding planes while the host rock of sandstone and shales remains relatively barren.
At the Northern Oxide Copper Zone located north of the open pit, the company will also be targeting mineralisation there with a drilling program, and the mineralisation is expected to be suitable for heap leaching.
This area has also been subjected to limited drilling with potential supergene and then primary mineralisation below the oxide mineralisation.
R3D Resources is a copper-gold explorer and developer in the Chillagoe Region in Far North Queensland, and the company owns several projects with the most advanced being the Tartana mining leases.
Tartana contains an existing heap leach, solvent extraction and crystallisation plant.
R3D also states work has commenced to restart this plant to provide future cash flow through the sale of copper sulphate.
In Tasmania, the company has secured permits to excavate and screen for ‘low-grade’ zinc furnace slag and matte fro its Zeehan stockpiles in western Tasmania, and it has been shipping zinc slag to South Korea.
These two projects have the potential to generate a strong cash flow to underpin the company’s ‘extensive’ exploration activities in the Chillgoe region.