Sampling returned assays of up to 1,347 g/t silver, 5,624 g/t indium, 5.7% copper, 15.4% lead and 17.3% zinc and 5.2% tin.
Red River will now work to convert the historical reserve estimate at Isobel to a JORC 2012-compliant resource and will complete geological mapping and sampling to define further extensions to known mineralisation.
The first six samples were collected from the main Isabel mine mullock and the next three were from mullock around a small shaft beside the track.
Four samples were from mullock at the northern shaft, five were from the Isabel Extended area and three from mullock at a shaft on the side of the hill.
Sampling has confirmed the presence of exceptionally high-grade polymetallic massive sulphide mineralisation in the project area.
Converting historic reserve
Isabel hosts one of the two known highest-grade silver-indium deposits in Australia and both have been granted to RVR.
Extensive work was carried out on the Isabel deposit in the early 1970s, culminating in the completion of a feasibility study and definition of a non-JORC compliant ore reserve.
The historical reserve is 83,236 long tonnes at an average grade of 15.3% zinc, 2.8% lead, 0.7% copper, 3.7 ounces silver, 12.1 ounces indium and 25.5 ounces cadmium per tonne for the Isabel deposit and this is within 100 metres of the surface.
Red River plans to acquire unreleased historic drill data on EPM27221 from the Department of Natural Resources, Mines and Energy and then complete drill targeting to convert the Isabel resource to a JORC 2012-compliant resource.