North Stawell Minerals
ASX Announcement
20 April 2022
Glenorchy East & Gready Prospects return Gold anomalies
AC drilling continued to return encouraging grades for potential follow up infill drilling.
Highlights:
• Aircore drilling continues to identify gold-anomalous geology in newly interpreted structural settings similar to the multi-million ounce Stawell Mine.
• Targeting gravity-only geophysics anomalies (i.e no strong magnetic signature) has successfully identified additional basalt geology - a principal pathfinder to gold-bearing structures.
• The program continues its first pass test of 20 key targets. Following the first pass drilling, most encouraging areas will be returned to for infill drilling.
• NSM is fully funded to execute its exploration activities with $10.0m cash at December 30, 2021.
Victorian gold explorer North Stawell Minerals Ltd (ASX:NSM) (North Stawell or the Company) is pleased to provide an update on its exploration programs. The aircore rig has continued the regional, first pass drill program, targeting mineralisation beneath shallow cover that has potential to be structural repeats of the multi-million ounce gold deposit at Stawell.
NORTH STAWELL MINERALS LTD
ACN 633 461 453
ABN 84 633 461 453
Figure 1. NSM tenure map highlighting areas with planned aircore drilling and RC drilling. The image also shows the position of the Stawell Gold Mine, major interpreted structures, the edge of the Murray Basin cover, approximate depth to basement and historic drilling collars with gold anomalism based on individual assays grades downhole.
North Stawell Minerals Ltd
Level 12, 644 Chapel Street, South Yarra, 3141 Victoria, Australia
2
Telephone +61 3 5358 1022www.northstawellminerals.com
NORTH STAWELL MINERALS LTD
ACN 633 461 453
ABN 84 633 461 453
North Stawell Minerals Chief Executive Russell Krause said:
"Results for the aircore program at the Glenorchy East and Gready prospects have been returned and include encouraging anomalous gold intercepts in two prospects. The targets locally have very weak magnetic signatures and have been identified using only high resolution gravity data. This is an important success for the exploration team, further demonstrating that the targeting methodology is effective.
Both Glenorchy East and Gready's are interpreted to have thick accumulations of basalt core - a close analogy to the structural setting observed in the multi-million ounce Stawell Mine.
NSM now has results returned for five priority prospects. Four of them have returned encouraging and anomalous gold results that warrant follow up with tighter spaced drilling. Three of the prospects are previously untested, and based on successful targeting with recently acquired, high resolution geophysics data, including gravity-only targets, new for exploration under cover at Stawell. The targeting successes continue - broad gold bearing intercepts are interpreted to indicate potential for nearby significant mineralisation - opening up additional targets for continued exploration.
Field teams continue to refine and improve surface saltwater management issues, evidenced by continuously increasing drilling meters. Feedback from landholders is positive, and strongly suggests surface management is sustainable with farmers and other stakeholders over multiple field seasons.
Exploration remains focused on testing the best targets with first pass drilling through the current drilling season to make sure follow up drilling is correctly applied to the prospects with the greatest chance of returning maximising shareholder value.
NSM regards the northern Stawell Mineralised Corridor, in which NSM now has a commanding ground position, to be one of Australia's most prospective and historic gold provinces and presents a target rich environment. Many prospects are already demonstrated to be gold mineralised and we are excited to update shareholders on progress.
Results including thick intercepts of anomalous gold are highly encouraging from the AC rig, indicating that a more substantial mineralised shoot may be nearby. The rig has moved on to other target areas, and is tasked to test as many as twenty priority targets during the drilling season, and will return to targets with better gold results to explore for the nearby source of anomalous gold results in first pass drilling.
An RC rig is on site and has started drilling several priority targets that are better suited to a rig with deeper drilling capabilities - particularly in the southern tenements.
Exploration Strategy
North Stawell Minerals is exploring for repeats of the multi-million ounce Stawell Mine under a thin blanket of post-gold mineralisation sedimentary cover (the Murray Basin). A distinct advantage of exploring for this type of mineralisation is that a basalt core controls mineralisation sites, and the basalt can be remotely mapped with geophysics (ie through the
North Stawell Minerals Ltd
Level 12, 644 Chapel Street, South Yarra, 3141 Victoria, Australia
3
Telephone +61 3 5358 1022www.northstawellminerals.com
NORTH STAWELL MINERALS LTD
ACN 633 461 453
ABN 84 633 461 453
blanket of cover). A high resolution airborne gravity survey conducted in the June Qtr FY21 completed the data suite required to efficiently explore, and an aircore rig has been testing regional resultant targets since October 2021.
Within the basalt structures, additional targeting is possible. Observations of controls on mineralisation in the Stawell Mine and modelling of ore-controls indicate that mineralisation is most likely to occur on the contacts (or in the metasediments proximal to the contact) of basalt cores where there are changing geometries coincident dilation zone (fold hinges, embayments, etc) where space for mineralisation is created. Where these locations are interpreted in geophysics, drilling is prioritised.
Glenorchy East
At Glenorchy East, 21km along strike to the north of the Stawell Mine (Figure 1), 27 holes for 1,804m were completed, comprising tests two parallel gravity targets (Figure 2, Figure 4).
The western gravity target includes a coincident magnetic high on a regional footwall thrust, with a single historic RC drillhole (GLOR21 (drilled in 1980)) testing the 1,500m long feature.
Only the northern end of the target was drilled on its east flank (7 holes for 500m), intersecting metasedimentary hanging wall rocks. Drilling returned 9 m at 0.12 g/t Au from 48m (NSAC0100), an encouraging wide anomalous intercept. GLOR21, drilled 500m south, terminated in basalt, indicating the highly prospective basalt contact is preserved at depth at NSMs target area.
The eastern target has a variable magnetic response, and never drill-tested. 20 holes were completed for 1,304m and typically intersected basalts. Drilling confirms the feature is basalt (demonstrating that a coincident magnetic anomaly is not imperative to this rock type being identified in data) but typically failed to test the prospective margins based on a Stawell Mine structural model. The correlation between the drilling and geophysics, however, indicate that the underlying structure can be confidently interpreted as 400m wide and 4,000m long, with untested potential where the basalt core plunges deeper and the contact with sediments is preserved. The sole result in the eastern target was 3 m at 0.3 g/t Au from 60m (NSAC0107) was returned - an encouraging anomalous gold intercept.
Gready
The Gready target tested an interpreted thrust repeated basalt with 35 holes for 2,152m of aircore drilling (Figure 3, Figure 4). The drilling was characterised by encouraging geology that included clear sericite and chlorite alteration as well as elevated sulphide content (pyrite and arsenopyrite) and demonstrated basalt. Best result was 6 m at 0.41 g/t Au from 37m (NSAC0150), occurring on the east flank near the contact with sediments. The result occurs at the south end of a 900m arsenic anomaly in data that runs the length of target and has minor gold anomalism along strike.
Later follow up drilling will target of the broader anomalous results that is open along strike.
No significant gold results (>1g/t Au) were returned in the Glenorchy East and Gready aircore program. Re-splits of 3m composites are not yet returned.
North Stawell Minerals Ltd
Level 12, 644 Chapel Street, South Yarra, 3141 Victoria, Australia
4
Telephone +61 3 5358 1022www.northstawellminerals.com
NORTH STAWELL MINERALS LTD
ACN 633 461 453
ABN 84 633 461 453
Anomalous gold results (>0.05g/t Au) at Glenorchy East and Gready are summarised in Table 1.
Table 1 Anomalous gold results, Glenorcgy East and Gready Prospect
Hole IDProspectEastingNorthingRLAzi.
DipFinal DepthResults AnomalousMGA54
MGA54
asldegdeg
(m)
(g/t Au)
NSAC0100 Glenorchy E
NSAC0107 Glenorchy E
648441 649366
5913631 5913690
151 151
0 0
-90 -90
73 9 m at 0.12 g/t Au from 48m
67 3m at 0.3 g/t Au from 60mNSAC0132
NSAC0132
NSAC0134
NSAC0137
NSAC0138
NSAC0150
NSAC0151
NSAC0152
Gready Gready Gready Gready Gready Gready Gready Gready
643041
5925798
151 0
-90
70 3 m at 0.09 g/t Au from 32m
643041
5925798
151 0
-90
70 3 m at 0.09 g/t Au from 65m*
642462
5925644
151 0
-90
68 6 m at 0.065 g/t Au from 51m
642756
5925636
151 0
-90
52 3 m at 0.09 g/t Au from 36m
642760
5925903
151 0
-90
76 3 m at 0.11 g/t Au from 55m
641875
5925547
151 0
-90
66 6 m at 0.41 g/t Au from 37m
641967
5925542
151 0
-90
60 3 m at 0.05 g/t Au from 45m
641256
5925446
151 0
-90
57 2 m at 0.06 g/t Au from 55m*
* Drillhole ends in anomalous grades
Anomalous results include grades >0.05g/t Au. Grades are combined into composites where adjacent assay results have an average grade greater than 0.05g/t Au. No internal or external dilution is applied. Stated thicknesses are downhole and unlikely to be represent true mineralisation widths.
North Stawell Minerals Ltd
Level 12, 644 Chapel Street, South Yarra, 3141 Victoria, Australia
5
Telephone +61 3 5358 1022www.northstawellminerals.com
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