Mt Stirling Gold Camp

Mt Stirling Gold Project

The Mt Stirling Project is located 40km northwest of Leonora in Western Australia (Figure 3). The Project lies 8km NW of Red 5's (ASX:RED) King of the Hills gold mine, which has produced in excess of 1 million ounces of gold to date. Current unmined resources are believed to be in the order of 3.1 million ounces at an average grade of 1.5 g/t Au.

The Leonora Gold District in the Eastern Goldfields has produced approximately 14m oz and is host to St Barbara’s (ASX:SBM) 4.8Moz Gwalia Mine and Saracen’s (ASX:SAR) 3.8Moz Thunderbox Mine  

The Mt Stirling Gold Project is divided into two blocks (Figure 1): 

  1. The Mt Stirling Block to the north 

  1. The Diorite Block to the south 

Mt Stirling Gold Project Figure 1. Torian’s Mt Stirling Gold Project holdings, 1) Stirling Block, and 2) Diorite Block. 

 

Mt Stirling Block

There are two different styles of gold mineralisation at Mount Stirling:

  • The Mt Stirling mineralisation is accommodated within a northeast dipping sheared mafic (Hi Mag Basalt),
  • Whilst the Mt Stirling Well is hosted by a quartz vein dipping shallowly to the east, fully contained within a granite.

In late 2018, Torian commissioned independent contractors to estimate the current gold resource contained within the project.  The current inferred Resource for the project is shown in Table 2.

Table 2: Mt Stirling Project Resource Estimation (FEB 2019)
Mt Stirling Project
JORC (2012) Inferred Resources - Gold >0.5 g/t 
     
Deposit Tonnes Gold g/t Ounces
Mt Stirling 727,000 1.45 g/t 33,895
Stirling Well 253,500 2.01 g/t 16,384
Totals 980,500 1.594 g/t 50,279


With these Mineral Resource Estimates, a solid foundation for future growth can be established. In doing so, strike and depth extensions of mineralisation require testing, and infill drilling will need to be undertaken to increase confidence in the current resource. The next round of resource expansion drilling campaigns in the Leonora Region will target these areas, seeking to build the resource base, towards a level that can sustain future mining operations.

Mt Stirling

In June 2020, Torian completed an 8 hole drilling campaign at the Mt Stirling Resource. The drilling campaign was successful in that it proved that the current gold system extends to depth, following high grade gold being intercepted 100m below prior drilling. (Figure 2)

Based on an analysis of the drill data from this campaign, it was determined that the Main Zone mineralisation has a very steep plunge to the northwest. Insufficient holes were drilled at depth during Phase 1 to define the plunge line of the mineralisation. Additional drilling will be completed to the northwest to follow down and further define the plunge of the mineralization to depth during the Phase 2 program scheduled to begin in Q3 2020. 

Mt Stirling

Figure 2. Section 1640 N showing Main Zone, Hanging Wall Zone, and future drill hole trace of future deeper R/C drilling. 

Mt Stirling

Figure 3. Longitudinal Section showing Grade x Width Contours, Plunge of the Main Zone and Hanging Wall (Red) Zone 

Phase 1 drilling also demonstrated that there appears to be a high-grade splay (33.10 g/t over 1.0 m) off the Main Zone sitting in the hanging wall (Figure 2 and 3). This high-grade splay seems to correlate with the heart of the Resource  contained within the Oxides facies of the deposit. Future drilling will focus on following this splay to depth in the attempt to define a high-grade underground shoot for future exploitation.  

High grade gold intercepts from historical and recent drilling campaigns at the Mt Stirling Block include:

  • 4m @ 12.98 g/t Au
  • 8m @ 3.07 g/t Au
  • 2m @ 26.9 g/t Au
  • 4m @ 5.33 g/t Au
  • 2m @30.3 g/t Au
  • 35m @2.99 g/t Au
  • 4m @884 g/t Au

Mt Stirling Well

As a part of the Q3 drilling campaign on the Mt Stirling Gold Project, the company intends to further explore the extent of the exisiting Stirling Well resource (Figure 4)

Mt Stirling Well

Figure 4: Mt Stirling Well cross section

 

The Diorite Block

The Diorite Project is located 40km northwest of Leonora in Western Australia (Figure 1) and is immediately south of Torians Mt Stirling Project. The Project lies 4km NW of Red 5's 4Moz King of the Hills gold mine. 

This was a strategic acquisition by Torian of the land immediately south of the highly prospective Mount Stirling Project. The tenure covers the continuation of the same suite of rocks that contain Mount Stirling and the 4 gold mines to its immediate east. Further Diorite is host to the historic 73 g/t Diorite King mine as well as a number of other high grade historical mines. (Table 1)

Table 1. Historical gold production and grade from mines in the Diorite King area. 

Mine 

Production Period 

Ore 

(tonnes) 

Average Gold Grade (g/t) 

Gold Produced (ounces) 

From 

To 

Diorite King 

1897 

1922 

1134 

73 

2,917 

Young Australian 

1897 

1899 

116.34 

34.3 

140 

Kiora 

1900 

1901 

87.38 

22 

69.5 

Lady Mae 

1902 

1905 

95 

23.3 

81.5 

Meteor 

1902 

1906 

88.4 

11 

34.2 

Rose of Diorite 

1908 

1908 

189 

18.7 

124.5 

Diorite Queen 

1909 

1909 

146.4 

9.8 

50.8 

Unexpected 

1922 

1923 

119.38 

47.2 

198.9 

Wotan 

1937 

1938 

100 

73 

257.8 

Source: Mindat.org

In June 2020, Torian conducted a rock chip and soil sampling campaign on the Diorite Block. Highlights from the campaign included:

  • 21 g/t gold and 2.10 g/t silver from the historic Unexpected mine dump.

  • 9.04 g/t gold and 9.59 g/t silver from the historic Unexpected mine (in-situ) 

  • 6.09 g/t gold from the historic Unexpected mine (in-situ) 

  • 7.49 g/t gold and 0.96 g/t silver from the historic Diorite King shaft (in-situ) 

  • Diorite soil sampling program returns high grade results up to 5.52 g/t gold from the Kiora/Meteor historic mine area 

The company was particularly encouraged by the fact that some of the higher grade discoveries were made in and around the high grade historical mines. This has propelled the company to advance it's exploration on Diorite with a 8,000 - 10,000m campaign planned for Q4 2020.

A total of 157 soil samples were collected from the Diorite Block. High grade gold assay values of 5.52 g/t Au (DIS002) and 3.2 g/t Au (DIS001) were collected adjacent to the historic Kiora and Meteor mines. A total of 89 soil samples returned anomalous gold values > 5 ppb. 

Figures 5 and 6 (below) show combined soil sample locations from June 2020 (157 samples) and historically (268 samples) over geochemical imagery of gold and arsenic in soils respectively. Figure 2 demonstrates that gold path finder element arsenic (As) correlates moderately with the gold in soil samples. 

 

 

Figure 5. Geochemical gold in soils heat map showing soil sample locations collected in 2020 and historically. 

 

Figure 6. Geochemical arsenic in soils heat map showing soil sample locations collected in 2020 and historically. 

 

Figures 7 and 8 shows the Company’s combined rock chip sample locations from June 2020 (105 samples) and historically (86 samples) over geochemical imagery of gold and arsenic in soils respectively. Figure 8 demonstrates that gold path finder element arsenic (As) correlates moderately with gold in rock chip samples. 

 

 

Figure 7. Geochemical gold in soils heat map showing rock chip sample locations collected in 2020 and historically.