Pioneer is in joint venture with Australian Mines Limited (AUZ) to explore and develop nickel sulphide resources within the Golden Ridge Joint Venture (GRJV). The immediate Blair Sulphide Nickel Mine area (operated by AUZ) is excluded from the GRJV, as are all gold rights. Currently Pioneer hold 56% interest in the joint venture with AUZ equity being 44%.
The GRJV covers an area of approximately 100 square kilometres of highly nickel prospective tenements covering more than 20 strike kilometres of ultramafics of the Golden Ridge Belt, which host the Blair and nearby Carnilya Hill nickel sulphide mines. As the tenure is mostly granted mining leases, in close proximity to the Kambalda concentrator, a nickel sulphide discovery could be brought into production quickly.
The Blair Nickel Mine (excluded from the GRJV) has produced in excess of 40,000t of nickel from underground workings at a average grade of approximately 2.53% Ni.
The Golden Ridge Ultramafic Sequence is a series of north-northwest striking, westerly dipping ultramafic, mafic and sedimentary rocks. The sequence is folded, with mafic-sediment-cored antiforms and ultramafic-cored synforms. The basal contact to the ultramafic is commonly felsic sediment ranging from argillite to greywacke. The ultramafic rocks are komatiites displaying high MgO and low MgO differentiates. Chert and sulphidic black shale is commonly present as contact and interflow sediments within the ultramafics.
Within the joint venture area the majority of the prospective basal contact is under alluvial cover. Previous exploration in the project area has concentrated in areas were the cover is shallow and insitu regolith is exposed. The Blair Mine was identified from a subcropping gossan and a number of sub economic concentrations of disseminated nickel sulphides have been identified at Blair South, Anomaly 11, and Area 20SW, Marshall, which point to the fertility of the ultramafic units within the joint venture area.
During 2008 the joint venture completed a major review of the existing exploration data on the project which resulted in a revised geological interpretation of the project area and helped define prospective ultramafic horisons, and generated a number of new nickel sulphide anomalies which are based on geochemical profiling of the ultramafic sequences.
The new targets are on the Leo Dam ultramafic which may be an extension of the contact that hosts the Blair nickel mine and the Central ultramafic belt were four new targets have been identified.
The Central ultramafic targets are less advanced than the Leo Dam Prospect. Based on broadly spaced regional air core drilling, three prospects (C2, C8, and C16) all with anomalous nickel, copper and PGEs have been identified over a strike of approximately 5 km. All the prospects appear to occur on the same ultramafic unit within a sequence similar to be Blair South Nickel Deposit.
Better results form the drilling to date are:
Exploration along the Central ultramafic belt is still in the early phases.
Detailed EM surveys were completed March 2011 covering six anomalies. Previously reported surveys completed late in 2010 located three priority conductive bodies on ultramafic surfaces interpreted to be free of conductive sediments, and another 3 conductors in prospective geological locations.
The present surveys were designed to better resolve the depth and orientation of targets before drill testing. The highest priority target is located east of, and on the same ultramafic contact as, the Blair Nickel Mine, which closed in December 2008.
The results from the recent SAMSON EM surveys at Golden Ridge led to the following key points from the interpretation:
Pioneer’s consultant geophysicist has recommended drill holes to test these targets.