Youanmi Gold Mine Project (Four JVs)

Youanmi (located 480km to the northeast of the city of Perth) is one of the last big WA gold mines to be re-examined for production under today’s high gold prices of AUD $2,500/oz

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  • Youanmi has a JORC 2012 compliant indicated and inferred resource estimate of
    1,190,600 ounces of gold (Refer VMC ASX release 28 May 2018 & 29 June 2018)
  • Venus Metals and Rox Resources Ltd (RXL) have four separate Joint ventures in the project area - OYG JV (Venus 30%; RXL 70%), VMC JV, Youanmi JV (Venus 50%; RXL 50%) and Currans Find JV (Venus 45%; RXL 45%) (ASX releases 21 June 2019 and 15 April 2019) (Figure 1). 
  • Approximately 24,000m RC drilling program has been completed in the OYG JV tenements.
  • Drilling at the Youanmi Gold Mine intersected new gold mineralisation at Grace Prospect (Figures 2a & 2b), Youanmi South and the Commonwealth Prospect. Deepest drilling completed at Grace Prospect has intersected impressive gold grades. 

Highlights include: 

RXRC287: 25m @ 34.79g/t Au from 143m (Grace) Including: 6m @ 140.7g/t Au from 150m (RXL ASX release 16 Jun 2020).

  • Deepest intercept to date extending mineralisation both along strike, and down-dip.
  • Grace is interpreted to comprise a series of north-plunging, high grade, stacked-lodes within the Youanmi granite. Grace is located adjacent to the historically-mined Youanmi shear zone hosted deposits located within the adjacent greenstone sequences. The Grace Prospect exhibits a ladder vein array geometry – a feature of other granite-hosted gold deposits of the Yilgarn Craton such as Granny Smith and King of the Hills. This style of mineralisation was not recognized at Youanmi by previous explorers (refer RXL ASX release 16 June 2020).
  • The funding of Venus’s exploration contribution in the OYG Joint Venture up until a decision to mine is by way of a limited-recourse interest free loan provided by RXL for Venus’s share of the ongoing costs (refer ASX release 16 June 2020). 
  • VMC has an overriding Royalty of 0.7% on all gold produced from the OYG JV.

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Figure 1. Youanmi Gold Project Ownership/Funding Structure

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Figure 2a. Grace Prospect-Drill hole collars and Intercepts over Aerial Photo

 

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Figure 2b. Grace Prospect Long Section (source: RXL ASX release 16 June 2020)

Geology

The Youanmi Gold Project straddles a 36km strike length of the Youanmi Greenstone Belt, lying within the Southern Cross Province of the Archaean Yilgarn Craton in Western Australia. 

The greenstone belt is approximately 80km long and 25km wide, and incorporates an arcuate, north-trending major crustal structure termed the Youanmi Fault Zone (YFZ). A series of northwest trending splay faults diverge from the YFZ providing a primary control on gold mineralisation traversing the steeply dipping basal greenstone stratigraphy. 

Gold mineralisation is developed semi-continuously over a strike length of 2,300m along the western margin of the Youanmi granite. The principal deposits include Youanmi Main, Hill End, United North, Kathleen, Rebel and Kurrajong 6. 

Exploration

The RC drilling program by OYG JV currently comprises a total of 270 RC holes for 23,471m in the Youanmi Gold Mine leases. 

The program aimed at testing new conceptual targets that have the potential to open up additional areas of mineralisation, better defining known sections of the significant Youanmi gold deposits.

Drilling at the Youanmi Gold Project intersected new gold mineralisation at Youanmi South and the Commonwealth Prospect, Grace Prospect (January 2020) and also other prospects (December 2019 drilling) (Figure 3) including:

  • RXRC287: 25m @ 34.79g/t Au from 143m (Grace) Including: 6m @ 140.7g/t Au from 150m; mineralisation extends both along strike, and down-dip
  • RXRC050 - 2m @ 23.67 g/t Au from 76m (Commonwealth)
  • RXRC049 - 4m @ 6.57 g/t Au from 64m (Commonwealth)
  • RXRC024 - 4m @ 8.17 g/t Au from 96m (Youanmi South)
  • RXRC013 – 5m @ 5.59 g/t Au from 81m (United North) including an intersection of 1m @ 23 g/t Au; RXRC014 - 9m @ 3.77 g/t Au from 58m (United North) including an intersection of 5m @ 5.93 g/t Au (refer RXL ASX release 9 September 2019)
  • RXRC158: 6m @ 46.51 g/t Au from 28m (Grace); RXRC151: 7m @ 54.6g/t Au from 8m; RXRC152: 1m @ 29.7g/t Au from 23m 
  • RXRC153: 6m @ 5.7g/t Au from 24m; RXRC154: 4m @ 4.5g/t Au from 9m, and 3m @ 5.32g/t Au from 53m
  • RXRC137: 4m @ 7.4 g/t Au from 60m (Youanmi South) RXRC140: 24m @ 1.5 g/t Au from 56m (United NE) (refer RXL ASX releases 9 September 2019, 18 February 2020, 2 April 2020 and 16 June 2020)

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Figure 3. Youanmi Pits Overlain on Geology with RC Drill Collars
(Figure also shows interpreted zones of relatively low pressure i.e. "pressure shadow" during displacement along Main Lode Shear Zone / gold mineralisation).

 

Drilling has defined a significant very high-grade zone of mineralisation (greater than 30 gram-metres) extending from surface and open to the north that lies within a broader zone of mineralisation. 

It is currently interpreted as a northerly plunging, high-grade, gold mineralised body; in places multiple shoots are present. 

Widenbar and Associates estimate a near-surface exploration target* of 2.0 to 2.6 million tonnes at 1.05 to 1.30 g/t Au and a Deeps exploration target* of 135,000 to 200,000 tonnes at 10 to 15 g/t Au. Importantly, these targets are in addition to the JORC 2012 Resource Estimates already provided (ASX release 29 June 2018) and predate the Grace gold discovery in granites. 

* An estimate of the exploration target potential of a mineral deposit in a defined geological setting where the statement or estimate, quoted as a range of tonnes and a range of grade, relates to mineralisation for which there has been insufficient exploration to estimate a Mineral Resource. 

 

Youanmi Regional Gold Exploration Projects

  • VMC has an extensive tenement holding in the Youanmi Greenstone belt in Western Australia and the Company holds exploration rights north and south of the historical Penny West high-grade gold deposit. 
  • VMC has currently been actively pursuing exploration activities within the Currans Find JV area containing the Currans Find Prospect and the VMC JV area containing the Sovereign Prospect and the Penny West Deep South Prospect.

Currans Find Prospect

  • RC drilling by VMC targeted shallow high-grade gold mineralization at the two main gold prospects ‘Currans Find North’ and ‘Red White and Blue Workings’ and their interpreted down-plunge extensions (Figure 4).
  • Drilling confirmed the presence of two stacked lodes at Currans North and shows an increase in gold grade and width in the Upper Lode which remains open at depth and down-plunge.
  • Historic Currans Find Mining Lease records show that 6,874 tons were treated at the Red White and Blue battery on site for a recovered average grade of 13g/t Au.

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Figure 4. RC Drill collars at Currans Find and Red White and Blue Prospects

Project background

VMC and RXL jointly acquired a combined 90% interest in ML 57/641 “Currans Find” of 300ha and a combined 90% interest in ML 57/642 of 59ha “Pinchers”. The 90% interest is shared equally between VMC and RXL, with the remaining 10% held by Mr Taylor. VMC is the manager of the joint ventures (ASX release 15 April 2019).  

Gold mineralization at Currans Find is hosted in multiple ENE‐trending quartz veins within mafic, intermediate and ultramafic rocks. These rock types are also host to the Penny West and Columbia –Magenta deposits south of Currans Find.

Exploration

RC drilling program by Venus JV targeted shallow high-grade gold mineralization beneath historical workings at the two main gold prospects ‘Currans Find North’ and ‘Red White and Blue Workings’ and their interpreted down-plunge extensions. 

The drilling confirmed the presence of two stacked lodes at Currans North and shows an increase in gold grade and width in the Upper Lode.  The results also demonstrate that the gold mineralization remains open at depth and down-plunge. 

Significant high-grade gold intersections from the RC drilling program at the Currans Find North include (Figure 4):  

  • CFRC26  - 3m @ 32.58 g/t Au from 115m including 1m @ 76.03 g/t Au from 115m
  • CFRC42  - 4m @   9.25 g/t Au from 46m including 2m @ 16.05 g/t Au from 48m
  • CFRC16  -   3m @ 27.5 g/t Au from 39m including  1m @ 72.67 g/t Au from 39m
  • CFRC14  - 2m @ 13.34 g/t Au from 61m including 1m @ 25.38 g/t Au from 61m 
  • CFRC31 -  3m @ 25.00 g/t Au from 109m including 1m @ 57.15 g/t Au from 110m
  • CFRC32   -  1m @ 39.61 g/t Au from 94m (Lower Lode)
  • CFRC46   -  1m @ 13.32 g/t Au from 110m (Upper Lode) and 2m @   3.84 g/t Au from 128m (Lower Lode)
  • CFRC47  -   4m @   5.28 g/t Au from   90m (Upper Lode) including   1m @ 15.30 g/t Au from  92m and 2m @   5.05 g/t Au from 111m (Lower Lode)
    (ASX releases 15 April 2019, 13 June 2019, 24 June 2019, 5 August 2019, 27 August 2019 and 5 September 2019)

 

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Figure 5. Interpreted longitudinal section showing high grade Au mineralisation at Currans North, with best AU intercepts from VMC drilling

The high-grade gold intersections from the RC drilling program at the Red White and Blue Reefs Prospect include (Figure 6):  

  • CFRC006 4m @   4.81g/t Au from 36m
  • CFRC007 3m @   1.81g/t Au from 52m
  • CFRC008 1m @   4.96g/t Au from 46m
  • CFRC009 1m @   3.51g/t Au from 9m
  • CFRC009a 1m @ 10.79g/t Au from 25m
    (refer ASX release 13 June 2019) 

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Figure 6. Interpreted longitudinal section showing high grade Au mineralisation at Red White and Blue Prospect, with best AU intercepts from VMC drilling

 

Penny West Deep South Prospect

  • The Penny West Deep South prospect is located south of the historic Penny West Mine.
  • A Heli-borne EM (HEM) survey was flown to target potential conductive horizons along the Youanmi Shear Zone. 
  • Five high-priority anomalies (PWDS1 to PWDS3, PWDS5, and PWDS13) were identified and are considered most significant as they lie south and along strike from the Penny West gold deposit and are adjacent to the interpreted Youanmi Shear Zone (refer ASX release 7 April 2020).

Project background

Venus JV comprises a 50% - 50% gold right only venture with Rox in which Rox earns 50% by spending $800,000 over 2 years and subsequently becomes a contributing JV with no further option to increase its rights. 

An Xcite Heli-borne Electromagnetic survey (HEM) was conducted at the Penny West Deep South Prospect (Figure 7) to delineate the potential conductive horizons along the Youanmi Shear Zone that may represent increased sulphide content potentially associated with gold mineralisation, similar to the setting observed at the historical high-grade Penny West Gold Mine and the Youanmi Gold Mine.

  • Analysis of the final HEM survey data, completed by independent geophysical consultants Core Geophysics, has highlighted 23 anomalies including 9 priority anomalies (ASX release 12 March 2020).
  • Five high-priority anomalies (PWDS1 to PWDS3, PWDS5 and PWDS13) are considered most significant as they lie south and along strike from the Penny West gold deposit, and are adjacent to the interpreted Youanmi Shear Zone (Figure 8). Modelling indicates the sources are near surface (from 50-80m vertical depth) and have moderate to high conductance (100-900S/m) with moderate strike and depth extents (100-200m) (refer ASX release 7 April 2020).

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Figure 7: HEM B-Field Z Channel 35 image showing priority anomaly outlines in red and labelled

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Figure 8.  High Priority PWDS_Xcite targets and AC drill hole locations on aeromagnetic imagery.

 

Sovereign Prospect

  • The Sovereign Prospect is located north of the historic Penny West Mine.
  • A magnetic low within which the Penny West gold deposit and the Columbia-Magenta prospects are located extends north into the Venus Joint Venture tenement (E57/1019) (Refer ASX release 12 August 2019) 
  • Initial AC drilling program intersected significant gold mineralization in VRAC151 4m @ 7.02 g/t Au from 24m, and 5m @ 2.41 g/t Au from 60m to EOH and in VRAC161 4m @ 0.94 g/t Au from 32m (refer ASX release 4 November 2019).
  • Immediate follow-up RC drilling confirm the presence of significant gold mineralization (YSRC05 3m @ 6.61 g/t Au from 78m including 1m @ 11.61 g/t Au from 79m) previously encountered in hole VRAC151.  

Project background

A magnetic low representing highly prospective settings for gold mineralization within which the Penny West gold deposit and the Columbia-Magenta prospects are located extends north into the Venus Joint Venture tenement (E57/1019) (Refer ASX release 12 August 2019).

Exploration

An initial AC drilling program targeted these highly prospective aeromagnetic trends and generated geochemical anomalies for lead and other base metals that may indicate the presence of Currans North and Penny West-style high-grade gold mineralization at depth. The drilling intersected significant gold mineralization in VRAC151  4m @ 7.02 g/t Au from 24m, and 5m @ 2.41 g/t Au from 60m to EOH) and in VRAC161  4m @ 0.94 g/t Au from 32m (Figure 7) (refer ASX release 4 November 2019).  

Immediate follow-up RC drilling commenced to verify gold mineralization encountered in AC holes VRAC151 and VRAC161 (Figure 9). The drilling program comprised 3 RC holes for 310m and results from YSRC05 confirms the presence of significant gold mineralization (3m @ 6.61 g/t Au from 78m including 1m @ 11.61 g/t Au from 79m) previously encountered in hole VRAC151. 

The newly discovered gold mineralization is associated with quartz veining in dominantly mafic schist with some ultramafic rocks. The gold mineralization broadly corresponds with anomalous lead and other base metal concentrations. This is considered significant as it resembles the association of gold with base metals observed at the Currans North and Red White and Blue Prospects (both Currans Find) and the historical Penny West gold mine.

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Figure 9. Location of Aircore holes shown on regional aeromagnetic image