Red River Resources Ltd (ASX:RVR) has increased its asset base after being granted new high-grade polymetallic silver-indium projects in northern Queensland hosting the highest-grade known indium deposits in Australia.
The new Isabel and Orient projects are near Herberton and around 500 kilometres from the company's Thalanga base metal operations.
Isabel includes the Isabel massive sulphide deposit with an average indium grade of 370 g/t and the Isabel extended exploration target while Orient includes the West Orient epithermal deposit with an average indium grade of 190 g/t and East Orient exploration target.
Red River continues to collate and model the historical data for both projects and after undertaking an initial site visit has started exploration activity.
Isabel massive sulphide deposit
Isabel deposit west of Herberton consists of massive zinc-lead-copper sulphide mineralisation containing indium and silver, occurring in fine-grained and breccia quartzites.
The sulphides are on both sides of a northwest-southeast trending quartz feldspar dyke.
Work completed on the deposit and vicinity included detailed mapping, geochemical soil sampling, underground sampling, geophysical surveying and both percussion and diamond drilling.
Great Northern Mining Corporation NL and Mareeba Mining and Exploration Pty Ltd carried out a 57-hole percussion and diamond drilling program during 1970-1972.
The known mineralisation at Isabel has not been constrained by the historical drilling and there is material potential to increase the historical resource.
Lady Isabel Extended
The Lady Isabel Extended target area is around 150 metres south of the Isabel deposit.
No recorded mining has taken place within the extended target area but numerous small diggings with shafts and development to about 6 metres depth or so are present.
In the early 1970s, Mareeba Mining completed geological mapping, soil geochemistry and an IP survey, followed by additional geophysical surveying, geochemistry and drilling in the early 1980s.
Six NQ diameter diamond drill holes targeting geophysical and geochemical anomalies were completed for a total of 1,1740.4 metres.
The Orient Project (EPM 27223) consists of the West Orient zinc-lead-silver-indium deposit and the East Orient exploration target, around 9 kilometres north of Irvinebank.
Silver-lead mineralisation was discovered in 1886 and mining activities ceased in 1924.
The lead-zinc-silver-indium mineralisation at Orient is believed to represent part of an epithermal precious metals system.
Great Northern Mining Corporation completed 16 diamond drill holes at West Orient, with the most recent drilling of four holes completed in 1988.
Geoscience Australia and other strategic partners of Australia, including the European Union, France, Japan, Korea, India and the United Kingdom, have defined indium as a critical mineral.
Indium, which is a critical element in low carbon technologies such as CIGS (copper-indium-gallium-selenide) thin film solar cells, is found in trace amounts in base metal sulphides, particularly chalcopyrite, sphalerite, stannite, and cassiterite.
Although indium’s concentration is highest within chalcopyrite, where concentrations are twice as high as in sphalerite, sphalerite remains the most important indium-bearing mineral for indium recovery.
The average indium content of zinc deposits from which it is recovered ranges from less than 1ppm to 100ppm. The indium reports to the zinc concentrate and is recovered at the smelting/refining stage.
Indium prices are currently around US$250 per kilogram.