Emu NL (ASX:EMU) has received promising multi-element assay results from the first-pass auger geochemistry programme at the company’s Viper project, located near Jerramungup in the wheatbelt region of Western Australia.
The results indicate significant copper anomalism along the Netty Dyke system extending East – West for more than three km in length. A second parallel feature has been identified 500m to the south of the dyke extending approximately two km in length.
The grid-based auger sampling programme was conducted by geological services contractors, Sahara Operations Pty Ltd in late February 2021. The maiden geochemistry programme was directed at testing the potential size and distribution of mineralisation associated with the historic Netty Copper Mine and its environs.
The programme completed a total of 153 auger holes which were drilled along 400m spaced North-South lines at a nominal 100m sample spacing over the largely granitic terrane and sampled from an average depth of 2m. Extra infill holes were drilled and sampled at 50m grid spacings along the projected trace of the East-West trending mafic dyke related to the high-grade copper mineralisation at the historic Netty Copper Mine.
The results have prompted Emu to plan infill lines within the current auger grid, and complete extra lines to the east and west to close-off the surface anomalies delineated and provide possible vectors towards deeper primary mineralisation along one or more of the geochemical trends established.
Sample analyses were completed by ALS Geochemistry (Malaga, Perth) using a multi-element super-trace (low-level) aqua regia digestion with an ICP finish to define the mineralisation in this apparently material but poorly understood mineral occurrence.
The geochemical samples were collected below the base of cover and areas of surface disturbance and comprised a representative one to two metre composite sample of in-situ soil/regolith. Four mineralised rock chip samples were also collected in the vicinity of the Netty Mine and sourced from this historical mining activity. All work was supervised by Sahara Operations’ principal consultant and geologist, Mr Beau Nicholls.
The multi-element assay results were processed and interpreted by EMU with specialist assistance from consultant geochemist Sugden Geoscience using industry-standard ioGAS software.
As expected, soil copper results were found to be highest around the historic workings (max 303ppm Cu), but, significantly, were found to continue both east and west over a span of at least 3km in a strong +50ppm copper trend supported by multiple element associations. This encouraging new multi-element trend is well supported by nickel (max 50.6ppm Ni), cobalt (max 43.3ppm Co) and zinc (max 147ppm Zn) and is found to be partially coincident with the projected trace of the mafic dyke exposed at the Netty Copper Mine (see geochemical distribution plots for Cu, Zn, Ni and Au shown in Figures 2 – 6).
A new, previously unsuspected, second parallel trend extending over at least 2 km was defined by the auger drilling approximately 500m south of the main trend. Whilst the anomaly is more subdued than the 3km trend reported above, peak values of copper (141ppm Cu), nickel (52ppm Ni) and cobalt (30.5ppm Co) are sufficiently encouraging to warrant EMU conducting follow- up evaluation.
Rock chip samples collected at surface from around the Netty Copper Mine returned copper values of >10,000ppm (limit of detection), 540ppm, 2,140ppm and 603ppm Cu respectively. High-grade copper was historically mined from the Netty Copper Mine.
Encouragingly, elevated gold assays were recorded in the east of the auger grid corresponding with arsenic (As), antimony (Sb) and bismuth (Bi) anomalism has also highlighted potential for gold mineralisation within the project area.
Emu has commenced planning for a follow-up field programme, which will include further infill and extensions to the auger soil grid, rock chip sampling and geological mapping.
Depending on outcomes from this programme, ongoing exploration will likely utilise geophysics to further define targets for drill testing. This programme will be planned to coincide with the completion of landowner harvesting activities.