The Clermont Au-Ag-Cu Project (100% IPT)


The Clermont Project is located about 20 km south east of Clermont and comprises one exploration licence EPM 14116 covering 79 sq km located in the prolific epithermal-intrusion related gold-silver belt in central Queensland, host to world class gold deposits such as Pajingo (Vera-Nancy) (>5 Moz of gold produced), Mt Leyshon (>3 Moz) and Mt Wright (>1 Moz) (Figures 1 and 2).

One third of the area is interpreted to be underlain by the prospective Cycle 1 Volcanics, beneath a cover of younger rocks and regolith. This cover has hindered previous conventional soil geochemistry surveys which identified a few areas, km in dimension, that contain anomalous gold values.

Figure 1. Location of the Clermont Project in the Drummond Basin, central Queensland.

Figure 2. Location of the Retro Fault System showing the Retro, Retro Extended and Nanya Prospects.

Work by Impact has now identified a two kilometre long target zone for high grade shoots of epithermal gold-silver-base metal mineralisation between the Retro and Retro Extended prospects at the northern end of the Retro Fault system. (Figures 2 and 3).

Figure 3. 3-D View looking towards the north west along the Retro Fault Zone showing high grade drill intercept at the end of a 2 km long target zone for high grade gold. The figure shows drill traces and 3D shells of the Z-scores for various metal assemblages and highlighting a proximal to distal transition from Retro, with an interpreted parent intrusion at depth, to Retro Extended.

The target has been identified from a pattern of strong metal zonation in drill hole assay data over at least 4 kilometres of strike of the Retro Fault Zone and a standout drill intercept of high grade gold-silver-base metals at the southern edge of the target (Figures 3 and 4).

Diamond drill hole RTIPT016, designed to test the down dip extension of previous modest drill intercepts at Retro Extended, intersected a 2.5 metre thick zone of quartz veins containing high grade gold silver and base metals (Figure 4). This zone returned a stand out drill intercept from 229.1 metres down hole of:

2.3 metres at 4 g/t gold, 59 g/t silver, 3% zinc, 1.9% lead, 0.3% copper and 100 ppm bismuth including

0.7 metres at 10.9 g/t gold 146 g/t silver 8.3% zinc, 5.1% lead, 0.7% copper and 310 ppm bismuth from 229.5 metres down hole.

This zone is interpreted to be the down dip extension of the thicker lower grade mineralisation intersected in previous drill holes and it appears to be in a position where the structure has a steeper dip. This indicates a strong, as yet unknown, structural control to areas of higher grade mineralisation.

Figure 4. Section 7,467,200 mN. Geology and assays for holes RTIPT016 and RTIPT007 with previous drill results.

The quartz veins show well developed mineral zonation with copper sulphide dominant at the edge of the vein through to dark brown to honey coloured zinc sulphides, and finally in the centre, colloform to crustiform quartz-chalcedony characteristic of epithermal veins (Figure 5). The copper and zinc sulphides are both intergrown with lead sulphide.

These textures indicate that the mineralisation is part of one evolving mineral system with progressive cooling of the parent fluid.

Figure 5. Diamond drill core from 230 metres downhole in RTIPT016. Copper sulphides (chalcopyrite) is yellow coloured at base of core; brown to honey coloured zinc sulphide (sphalerite) in the centre; and colloform to crustiform quartz-chalcedony in upper right.

The metal zonation is characteristic of epithermal mineralisation directly related to magmatic fluids released from a porphyry intrusion of intermediate composition and similar to the zonation associated with the world class Pachuca polymetallic mining district in Mexico.

In addition the vein system has a strong structural control and the focus of future drilling will be to identify thicker high grade shoots along the Retro Fault Zone.

This new interpretation is mostly based on new assay data from a drill programme completed in late 2018 which included the first diamond drill hole and the first full suite multi-element assays at the project.

Until this programme little was known in detail about both the nature of the gold-silver-base metal mineralisation and also the structural controls on the quartz veins.

Details on the drill programme and the interpretation which was completed in conjunction with well respected epithermal and porphyry consultant Dr Gregg Morrison, can be found in this announcement link.