Swan Trend
The Swan Mineral Resource is located in the main historic mining area just 700m from the historic Gidgee mill. The current MRE for the Swan and Swift open cut deposit is 12.7 Mt @ 1.1 g/t Au for 434,100oz. The open cut resource is confined to A$2,600/oz optimal pit shells. The current MRE for the Swan underground deposit is 0.5 Mt @ 7.0 g/t Au for 118,500oz.
Gold mineralisation in the Swan area is associated with conjugate quartz-carbonate-pyrite vein sets preferentially hosted within carbonate-sericite altered dolerite. Conjugate vein sets are shallow southeast dipping with lodes generally plunging to the south (i.e. Australia, East and Albania Lodes) and moderate to steeply northeast dipping with lodes plunging to the north (i.e. Monte Carlo, Sicily, Tunisia, Cascade and Premium) (Figure 1). High-grade ore shoots are parallel to vertical fold hinges within the dolerite and formed at conjugate vein set intersections and at the intersection of vein sets with the Butcherbird Shear Zone to the east. The vein sets, associated tension gashes and high-grade ore shoots have been subjected to later fault/shearing events resulting in localised orebody complexities.
The Swan Mineral Resource area is a large mineralised system with a strike length of 1.4km. The area retains excellent scope for potentially defining further shallow open cut and underground Mineral Resources beyond the previously mined and current resource area, particularly along strike to the north and down plunge on many of the Swan underground lodes including Monte Carlo, Monaco, East, Sicily, Tunisia, Cascade and Premium Lodes (Figure 1). Exploration drilling is focusing on the shallower zones within these targets with the aim of building on the existing open cut resources.
Significant intersections (>50 Au gram x metres) from the deeper parts of the Swan deposit that remain open down plunge of interpreted high-grade lodes include*:
- 14m @ 35.3g/t Au from 182.0m (GDC058)
- 7.4m @ 60.8g/t Au from 48.1m (GUD985)
- 10.7m @ 30.1g/t Au from 33.0m (GUD844)
- 10m @ 15.8g/t Au from 297.0m (SBDD080)
- 8.1m @ 19.2g/t Au from 106.9m (GUD1229)
- 6.3m @ 19.1g/t Au from 229.5m (GUD1212)
- 11.8m @ 5.6g/t Au from 127.5m (GUD887)
- 10.7m @ 5.2g/t Au from 292.6m (GUD915)
- 5m @ 10.6g/t Au from 257.0m (SBDD073)
- 12m @ 4.3g/t Au from 85.0m (JRC2548)
*Refer to Horizon Gold Ltd ASX announcement dated 15 February 2021, “Gum Creek Geological Review”. CPs L.Ryan, M.Gunther, D.Archer.
Figure 1: Swan Mineral Resource area long section showing open pits, underground workings, drill assays (Au g/t), and interpreted high-grade lodes, and gold intercept gram x metre pierce points for significant previous drilling intercepts that remain open at depth (labelled).
Figure 2: Swan deposit cross section (6983775N) showing mineralised envelope, significant gold intercepts and existing open pit.
Swift Trend
The Swift Mineral Resource is located 1.2km east of the historic Gidgee mill. The current MRE for the Swan and Swift open cut deposit is 12.7 Mt @ 1.1 g/t Au for 434,100oz. The open cut resource is confined to A$2,600/oz. optimal pit shells. The current MRE for the Swift underground deposit is 527,000t @ 5.7g/t Au for 25,400oz.
Gold mineralisation in the Swift area is also associated with conjugate quartz-carbonate-pyrite vein sets preferentially hosted within carbonate-sericite altered dolerite. Conjugate vein sets are shallow southeast dipping with lodes generally plunging to the south, and moderate to steeply northeast dipping with lodes plunging to the north (Figure 3). High-grade ore shoots are formed parallel to vertical fold hinges within the dolerite, at conjugate vein set intersections and at the intersection of vein sets with the Swift Shear which runs through the eastern edge of the Swift open cut mine.
The Swift Mineral Resource area currently has a strike length of 1.1km and retains excellent potential for defining further shallow open cut and underground resources beyond the previous mining and current resource area, especially along strike to the north of the Gannet open pit, and immediately below the Swift pit (Figure 3). Exploration drilling is focusing on the shallower zones along the Swift mineralised trend with the aim of building on the existing open cut resources.
Significant intersections (>40 Au gram x metres) from the deeper parts of the Swift deposit that remain open down plunge of interpreted high-grade lodes include*:
- 8m @ 14.8g/t Au from 130.0m (GDC179)
- 11m @ 8.8g/t Au from 282.0m (GDC013)
- 19m @ 4.7g/t Au from 119.0m (SBRC037)
- 16m @ 4.0g/t Au from 102.0m (GDC018)
- 12m @ 4.2g/t Au from 63.0m (JRC0944)
- 13m @ 3.8g/t Au from 131.0m (SBRC059)
*Refer to Horizon Gold Ltd ASX announcement dated 15 February 2021, “Gum Creek Geological Review”. CPs L.Ryan, M.Gunther, D.Archer.
Figure 3: Swift Mineral Resource area long section showing open pits, drill assays (Au g/t), and gold intercept gram x metre pierce points for significant previous drilling intercepts that remain open at depth (labelled).
Figure 4: Swift deposit cross section (6983225N) showing mineralised envelope, significant drill intercepts, and existing open pit.
Figure 5: Swift and Swan Resource areas looking north
Figure 6: Swan/Swift Open Cut MIK resource block model coloured by Au (g/t), and A$2600/oz Whittle pit shell outline (yellow) over satellite image
