White Rock Minerals (ASX: WRM) announced that six new, potentially significant, mineralised volcanogenic massive sulphide (VMS) targets were identified during the 2020 field season at its Red Mountain Project, Alaska. None of the six prospects are believed to have ever been drill tested.
Highlights of regional reconnaissance rock chip sampling from outcropping massive sulphides include Horseshoe (up to 8.3% Zn, 0.3% Pb, 1.1% Cu, 12g/t Ag & 3.6g/t Au); Bib (up to 7.3% Zn, 5.1% Pb, 0.3% Cu, 40g/t Ag & 0.3g/t Au); Bib West (up to 5.7% Zn, 1.4% Pb & 0.2% Cu); Grapple (up to 3.6% Zn, 1.9% Pb, 0.7% Cu & 40g/t Ag); Peaches (up to 2.9% Zn, 2.8% Pb, 0.2% Cu, 46g/t Ag & 1.5g/t Au); and Ringer (up to 1.0% Cu, 26g/t Ag & 0.4g/t Au).
White Rock said that more detailed ground magnetics, mapping, and systematic surface geochemical sampling are being planned for early during the 2021 field season with drill testing potentially to follow.
2020 field season at Red Mountain
The company had sampled new VMS prospects during the 2020 field season at its 100% owned Red Mountain Project, Alaska. Red Mountain hosts a VMS JORC Resource1 of 9Mt at 157g/t silver, 5.8% zinc and 0.9g/t gold, for a 13.2% Zinc equivalent2 (or 609g/t (19 ozs/t) Silver Equivalent3) grade.
WRM said that six new, potentially significant, mineralised VMS targets were identified during the follow-up of stream sediment anomalism identified at Red Mountain Project. The company said that the VMS outcrops (lenses) identified were composed of pyrrhotite (a magnetic iron-sulphide) or pyrite, sphalerite (zinc sulphide), galena (lead sulphide), and minor chalcopyrite (copper sulphide).
WRM said that the VMS lenses were coincident with podiform magnetic features identified by an airborne magnetics survey flown in 2020, and likely represent magnetic response of pyrrhotite within these VMS lenses thereby allowing magnetics to be modelled for definition of robust new VMS drill targets.
The company noted that the main productive VMS stratigraphic package between Gossan Peak and Peaches trends east-west over a strike length in excess of 13km with a thickness of 500 to 750 metres. VMS mineralisation occurs as discontinuous stacked lenses or pods parallel to the east-west regional foliation, proximal to second order northwest and northeast trending faults.
Regional rock chip sampling
Highlights of regional reconnaissance rock chip sampling from outcropping massive sulphides include Horseshoe – up to 8.3% zinc, 0.3% lead, 1.1% copper, 12 g/t silver and 3.6 g/t gold; Bib – up to 7.3% zinc, 5.1% lead, 0.3% copper, 40 g/t silver and 0.3 g/t gold; Bib West – up to 5.7% zinc, 1.4% lead and 0.2% copper; Grapple – up to 3.6% zinc, 1.9% lead, 0.7% copper and 40 g/t silver; Peaches – up to 2.9% zinc, 2.8% lead, 0.2% copper, 46 g/t silver and 1.5 g/t gold; and Ringer – up to 1.0% copper, 26 g/t silver and 0.4 g/t gold.
Similarities with Dry Creek and WTF
The company said that a number of the magnetic features coincident with VMS lenses can be interpreted over strike lengths of 1.0 to 1.5km, similar to the VMS deposit dimensions that make up the Project’s VMS JORC-compliant Resource further east at Dry Creek and WTF.
Parallel follow-up drill program
WRM said that it is also considering a parallel follow-up drill program at its large Last Chance Intrusion Related Gold System (IRGS) target, where collectively, there are approximately 30km2 of drainages shedding anomalous gold across the Last Chance property indicating excellent potential for discovery.
WRM said that planning is underway for the 2021 field season with proposed work including mapping, sampling, geophysics, and drill testing of VMS targets.
WRM said that it is planning to complete follow-up surface geochemistry and geophysics prior to the likely drill testing of the best VMS targets during the 2021 field season.