Rumble Resources Ltd (ASX:RTR, OTC:RTRFF) has received “an unexpected bonus” with the discovery of exceptionally high-grade tungsten mineralisation within the gold system at Western Queen Project in the Yalgoo mineral field of Western Australia.
Systematic pXRF analysis of diamond drill hole WQDD013 at the Western Queen South deposit led to ultraviolet scanning which highlighted significant scheelite zones.
Wet analysis of the main visible scheelite zone has confirmed the discovery as very high-grade tungsten skarn-style mineralisation with a best result of 4 metres at 4.58% WO3 and 0.72 g/t gold from 174.85 metres. This included 2.05 metres at 8.71% WO3 and 1.38 g/t gold from 176.85 metres and 0.65 metres at 18.35% WO3 and 2.97 g/t gold from 176.85 metres.
Supporting the tungsten find was a subsequent review of all pXRF data routinely collected by Rumble which showed that tungsten is widespread within the Western Queen gold mineralising system.
“Huge optionality”
Managing director and CEO Peter Harold said: “The discovery of the very high-grade tungsten at Western Queen is an unexpected bonus for us from the recent drilling which was targeting extensions to the high-grade gold lodes.
"While it is very early days the grades of the intersections are exceptional and well above the grades of other tungsten resources globally. We are now waiting with trepidation for the results from the 2021 drill pulps.
"This discovery shows the huge optionality of the Rumble tenements and the ability of our highly experienced exploration team to make new discoveries.”
Investors have welcomed the tungsten discovery and have driven shares up by 12.5% to A$0.036.
Western Queen Gold Project – resources, prospects and tenure over 1VD RTP Air Magnetics.
Strong tungsten anomaly
Rumble’s work has outlined a strong continuous tungsten anomaly over 2 kilometres from drill hole XRF data that parallels the Western Queen Shear and known high-grade gold mineralisation.
Tungsten occurs at surface between the Western Queen South and Western Queen Central open pits with widths up to 20 metres.
The mineralisation contains large aggregates of scheelite grains (up to 5mm) occurring parallel to the main foliation trend.
The skarn development is thought to have been a later stage to the main gold event at Western Queen.
Previous holes analysed
All previous drill holes completed by Rumble as part of the 2021 Western Queen gold resource estimate of 2.1 million tonnes at 2.42 g/t gold for 163,200 ounces have subsequently been analysed for tungsten by pXRF.
Review of this analytical data has shown 87 reverse circulation (RC) and diamond drill holes completed by Rumble have reported >500ppm tungsten.
Re-assaying of select pulps from the previous Rumble gold resource drilling programs based on the pXRF tungsten analyses is underway to ascertain the spatial variability and tenor of the scheelite mineralisation.
Up to 250 pulps from selected RC and diamond holes drilled by Rumble will initially be collected and submitted for wet analysis utilising complete digest through fusion XRF.
Location plan of the Western Queen Gold Project.
A critical raw material
Tungsten is classified as a critical raw material and is subject to high supply risk, limited substitution options and high economic importance.
The supply of tungsten, currently 78,000 tonnes annually, is highly dependent on China, which produces 81% of the world's tungsten.
Forecast demand at a compound annual growth rate averages 3.5%, however, certain projections have a more robust forecast of up to 8%.
Tungsten supply from China is forecast to decline due to diminishing reserves and grades making sources outside of China significantly more valuable.
Tungsten uses
Uses for tungsten include:
- Nano Tungsten Oxide for battery cathode and anode (Li-ion) manufacturing;
- Niobium Tungsten Oxide in batteries to reduce charge time and increase power density;
- Tungsten Hexafluoride gas to optimise all semiconductor production;
- Tungsten wire to essential replace diamond wire for photovoltaic cell silica wafer production;
- Tungsten Oxide coating to enhance hydrogen fuel cell durability;
- Use in thermonuclear energy – excellent heat conductivity and very high melting temperature. Includes 100% tungsten (100-200 tonnes per reactor) and high tungsten steel surrounding the reactors.
- Military applications.