Pinnacle Well Project


The company’s Pinnacle Project is comprised of a single large exploration license (E 37/1246) which was recently renewed for a 5-year period.  The area covered by the tenure is 9500Ha and the project is located approximately 25km north of Leonora adjacent to the Goldfields Highway.

Geological Setting

The project is located in the Archaean aged Yilgarn Craton of Western Australia and lies within the Kurnalpi terrane of the Eastern Goldfields Superterrane.  At a district scale, the Leonora area hosts numerous world-class gold deposits which include the Sons of Gwalia, King of the Hills, Thunderbox, Darlot and Agnew gold deposits.  Base metal volcanogenic massive sulphide (VMS) deposits such as Teutonic Bore, Jaguar and Bentley are located to the north.

The area is well structurally prepared with the interpreted structures being the regionally significant Keith-Kilkenny Shear Zone and the Pig Well Graben which is located in the southern portion of the tenements (host to the Gambier Lass mineralisation to the south).

Locally, the Bundarra batholith syeno-granite dominates the northern portion of the tenement. The Archaean bedrock greenstone sequence within the tenement consists of an interpreted andesite-dacite dominated sequence with lesser rhyolite which is intruded by the Christmas Well, felsic to intermediate composition, subvolcanic porphyritic intrusives.

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The project area geology is poorly exposed (only approximately 30% of the project area is out-cropping, predominantly to the north in granitoid lithologies) and presents largely as areas of moderate to intensely weathered subcrop and associated colluvial and alluvial cover. The remaining 70% of the tenement area comprises transported distal colluvial and alluvial deposits ranging from a few metres deep to tens of metres deep.

Previous Exploration

The area has had very limited drilling, despite the presence of a highly prospective greenstone belt, extensive alteration and structural preparation from the underlying Pig Well Graben and the district-scale Keith-Kilkenny Shear zone.  Wide spaced aircore with some localised RC and core drilling have been completed up to 2011 – with little activity since then.

The previous owner in the past five years collated existing data and undertook field mapping and sampling, resulting in the identification of various alteration styles with associated mineralisation potential.  Significant areas of hydrothermal alteration were identified, interpreted being associated with the structural preparation associate with the granitoid intrusion, the Keith-Kilkenny Fault and Pig Well Graben.

An extensive network of vein and gossan zones was identified that appear both associated with, and proximal to, the intense hydrothermal alteration.  The sampling and mapping confirmed the presence of gold, base metal and molybdenum mineralisation in numerous locations across the Exploration License.  Several significant gossans with potential for base metal mineralisation were located.

Rock chip sampling in the exposed quartz veining has returned assays of up to 12g/t gold with elevated silver and bismuth. Extrapolation of limited outcrop/sub-crop suggests two main gold mineralisation orientations, an east-west trend (sub-parallel to the granite contact) and the other trending NNW. The strike length of a number of separate quartz veining structures extends to several kilometres.

Exploration Programme

With approximately 70% of the tenement shrouded by recent alluvial cover, the majority of the interpreted mineralisation trends have had either no follow-up or very limited follow-up exploration. The previous targeting work will allow OZZ to undertake an immediate and more focused exploration effort leading to early drill campaigns.

Gold mineralisation will be the priority target, but a review of the base metal potential is expected to provide further targets.  Soil sampling and geophysical surveys will be planned to better localise targets with drilling intended in the second half of 2022.  Given the size and prospectivity of the lease area, Pinnacle Well will remain a key focus for OZZ.

The Pinnacle Well prospect is surrounded by extensive pyrophyllite alteration. Pyrophyllite (Al2Si4O10(OH)2) is a hydrated aluminum silicate, a talc group mineral.  Following previous explorer’s recommendations, further work will be undertaken to assess the commercial potential of the pyrophyllite mineralisation.