A reconnaissance phase of work starting in 2015 produced a substantial copper anomaly covering over 2 km2. An initial drill hole in 2018 tested the ground under some of the stronger copper showings and returned 45.7 m @ 0.27% Cu from 35.1 m. This work was followed by drone magnetometry in 2021, confirming a strong magnetic anomaly overlying the strongest parts of the soils anomaly and continuing to the southwest.
During fieldwork in 2023-2024 a significant area of previously unrecorded granite, the Crowne Point Granite (CPG), was mapped. This granite contained both copper showings and a wide array of textures indicating fluid release, which are typically found in porphyry-forming intrusions. Various additional small outcrops of the same phase of granite and related aplites have been mapped throughout the copper-in-soils anomaly.
Geophysics followed, with IP surveys taking place early in 2024. These surveys showed two key areas of anomalous chargeability:
- Associated with the strongest surface copper showings and extending, strengthening and plunging to the south and west, aligned with the magnetic anomaly. This anomaly is open on the southwestern-most IP profile.
- Under the edge of the sediments proximal to the northeastern parts of the West Huntoon range front. This anomaly is the stronger of the two, and both strengthens and grows to the northeast where it is open on the northwestern-most IP profile.
After the IP work, further soil sampling and field investigation established a continuing copper anomaly to the northeast, in the hills adjacent to the chargeability anomaly under the sediments. This area also hosts a swarm of aplite dykes and several copper oxide showings. Infill soil sampling was also deployed to the core of the prospect to better define drill targets along with the IP results.
West Huntoon occurs in a diverse range of host rock lithologies exposed on the northwestern margin of the Huntoon Valley. The core of the strong copper showings is hosted in strongly sheared rocks of likely volcano-sedimentary origin. These rocks were mapped by the USGS as belonging to the Mina Formation, which comprises volcano-sedimentary rocks with mafic porphyry intrusions.
Within this zone various previously unmapped examples of highly-evolved silica-rich granites and aplites occur, the principle exposure of which being the Crowne Pointe granite, which was mapped by the USGS as Tertiary volcanics (possibly as a result of its superficially similar appearance to a pale tuff horizon at the base of said volcanics in the area).
The Crowne Point granite contains copper showings along with miarolitic cavities, pegmatitic pods, unidirectional solidification textures, and locally intense stockworks of A-, AB- and B-type veins, all of which are characteristic features of granites which have released hydrothermal / mineralising fluids.
Further outcrops of this phase of intrusion have been identified at various locations around the West Huntoon area, and occurrences in the northeast, exposed at the edge of the tertiary cover, are linked to the continuing copper anomaly in this zone, sampled in summer 2024.
The copper anomaly is seemingly limited only where it disappears under post mineralisation cover, such as the Tertiary volcanic succession, and the Recent Huntoon Valley sedimentary infill. The only exception to this rule is to the southwest along the trend of the valley, where the anomaly weakens at surface over host rock exposures, however, the chargeability anomaly in this zone grows in strength and size while plunging to the southwest.
The area has been effected by a number of deformations and the rocks are highly sheared. The most recent movement is sinistral along the Huntoon Valley axis, along with a general block tilting towards the Huntoon Valley, as evidenced by the tilt of the Tertiary volcanic sequences which cover parts of the host rocks exposure in the hills.