Aruma has completed 6,243m of RC drilling at Salmon Gums, which consisted of the initial 2,298m in 33 holes and follow-up phase of drilling for 3,945 metres in 39 holes. The initial assays were reported in January (ASX announcement, 21 January 2022) with the last hole finishing in mineralisation of 4m at 4.26g/t Au. Assays have now been returned for some 27 holes and the remaining 12 holes are expected this month.

Assay results received to date further reinforce Aruma’s exploration model for the potential presence of a large gold system with significant mineralisation intersected over 4.3km strike and on granite-mafic contacts which greatly increases the target zones for the whole project. The identification of the Fault/Dome areas in the North of the lease and the identification of multiple high grade zones at Thistle-Iris are very promising.

The gold potential of the Salmon Gums project is shown by the proportion of holes hitting gold in the program. A total of 19 of the 27 holes assayed to date have recorded a gold value of greater than 0.1 g/t Au and of these 6 have intersected gold over 1 g/t with highest assays of 13.35, 18.3 and 224g/t Au.

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Table 1 Details of assay results >1.0g/t Au.

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Table 2 Details of Intersections with results >1.0g/t Au. Grid is GDA94.

The mineralisation is in mafic rocks near the granite contact, with quartz veing and sulphides evident with minor bleaching of the rock as shown in Figure 3 below.

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Figure 3: The drill chips from SGRC39 showing the mineralised zone with the quartz veining

Aruma completed a two hole, 701m diamond drilling program at the Salmon Gums Project in June (ASX announcement, 3 June 2022). Drilling was designed to provide a deeper geological understanding of the Project and has generated core samples to allow for definition of rock types, mineralisation types, metallurgy and stratigraphy, along with gold grades and controls.

Initial assays have returned anomalous zones of gold (Table 1). Also, of significant importance, core samples from the drilling have re-defined what were previously interpreted as granites to be sediments (Figure 2). This has resulted in an interpreted expansion of the width of the greenstone at Salmon Gums to in excess of 3km along a strike length of more than 25km – expanding the interpreted greenstone footprint to approximately 75km2.

The core exhibits characteristics of the regional greenstone with a corresponding lack of granite and intrusives, and data from the core has opened-up the potential for the Salmon Gums Project to host multiple horizons similar the major Scotia gold project to the north.

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Figure 1: Location map highlighting Salmon Gums, ~300km south of Kalgoorlie

This major interpreted expansion of the greenstone area warrants a dual exploration approach at the Project. This will incorporate detailed, targeted exploration on the Iris-Thistle trends over an area of 10km2 plus a regional assessment utilising known high-grade zones as signature patterns for other gold targets over the wider Project area.

Aruma has commenced an airborne high resolution magnetic survey to be followed by a ground gravity survey early in the new year, to generate targets for further drilling. This drilling is planned for the first quarter of 2023.

Diamond Core Drilling Commentary

Interpreted geology from initial examination of the core from the diamond drilling program indicates a wide sequence of sediments from the Noganyer and Woolyeener formations, similar to the Scotia belt to the north with no granite stoping evident in the drillholes. This has given the Project area a wider prospective zone than initially interpreted for multiple horizons similar to Scotia.

The Salmon Gums greenstone belt shows subtle stratigraphy on currently available coarse magnetics and can now be demonstrated to be wider than 3km. This will be refined with high resolution magnetics to be which is currently being flown.

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Figure 2: The intersected volcaniclastics of the Woolyeener Formation in SGDD01

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Figure 3: The cross section on the Thistle line at 6,361,620mN showing stratigraphy

The interpreted cross section of the Thistle Line shows the stratigraphic contact position of the mineralisation (red) with the Arkosic wacke (pink, previously logged as granite), siltstone (blue), mafic (green) and ultramafic (purple) units (Figure 3). The position of the mineralogy is typical of lode deposits on contacts.

The key outcome of the initial assessment of the new diamond core was the lack of granite and intrusives, and the soft sediment slumping and folding demonstrating the wet porous sedimentary tuffaceous nature of the greenstone belt. This porosity and contained fluids are critical for hydrothermal gold deposits.

The diamond drilling followed-up Aruma’s maiden wide-spaced RC drilling program at Salmon Gums which returned exceptional high-grade gold intersections (ASX announcement, 21 March 2022), including;

  • 5m @ 50.2g/t Au from 42m in hole SGRC39 including
  • 3m @ 83g/t Au from 42m and
  • 1m @ 224g/t Au from 44m
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Figure 4: The Iris and Thistle Trends at Salmon Gums with drill holes and geochemistry

The interpreted geology of the area demonstrates layers of volcaniclastics, flows and pillows that are reported at Scotia (Figure 4). Figure 5 (a, b and c) shows the progressive increase in understanding of the extent of the greenstone south of the Jerdacuttup Fault within the Salmon Gums Project area.

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Figure 5. Showing the progression of the understanding of the southern extents of the Norseman-Wiluna greenstone belt.

Figure 5a. Pre 2000 the GSWA interpretation has the Jerdacuttup Fault as the southern extent of the Norseman-Wiluna terrain of the Yilgarn, and the Salmon Gums area to be part of the Albany-Fraser Orogen. Figure 5b. shows the approximate known width of the greenstone following Aruma’s RC drilling in 2022. Work undertaken by Pan Aust in 2003 identified gold anomalism.  Scotia was mined ~2005 by Croesus Mining.  The Scotia Project is south of the Jerdacuttup Fault and is mapped as a high metamorphic grade Norseman greenstone sequence consisting of basalts, banded iron sediments and shales. Figure 5c. is interpreted greenstone sequence following Aruma’s recently completed diamond drilling, highlighting the extra width of greenstone. 

About the Salmon Gums Gold Project 

The Salmon Gums Project (EL63/2037, EL63/2122, and ELA63/2303) covers a total area of 396km2, and is located 200km south of Kalgoorlie, and 60km south of the mining town of Norseman. The Project is situated 30km south and directly along strike, in the same stratigraphy, as Pantoro Limited’s (ASX: PNR) rapidly expanding high-grade Scotia Gold Project.

Aruma has completed a total of 6,243m of RC drilling in its maiden drilling program at Salmon Gums. This consisted of an initial 2,298m in thirty three holes and a follow-up phase of drilling for 3,945 metres in thirty-nine holes.

This drilling reported exceptional high-grade results (ASX announcement, 21 March 2022), and further reinforced Aruma’s exploration model for the potential for the Project to host a large gold system.

Significant mineralisation was intersected over a 4.3km strike and on granite-mafic contacts, which greatly increased the target zones for the whole project. Fault/dome areas were identified in the north of the Project plus the multiple high-grade zones at the Thistle-Iris trends.

The interpreted quantum expansion in greenstone area at the Project from approximately 15km2 to up to approximately 75km2 will require a twofold exploration strategy. There will be detailed exploration on the Iris-Thistle trends covering 10km2 plus a regional assessment using the known high grade zones as signature patterns for other gold targets over the larger area. The size of the belt to be investigated is shown in the comparative area at Scotia shown in Figure 5.

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The Salmon Gums Project area with laterite and quartz veins (inset)