Drilling for water at Clunes - February 2008

Drilling at Clunes January - February 2007

Cut and sample program coreshed Allendale
Diamond drilling recommences Site 2 January 2007. Photo looking west
Deepening Hole CD06-6 early February 2007. Photo looking southeast Site 2

Click on diagram to enlarge


For further explanation of the Mineralogical Report and photos below see Company Announcement dated 19 January 2007 on National Stock Exchange of Australia website www.nsxa.com.au


Hole CD06-2

Sericite-slate or phyllite with numerous scattered euhedral crystals of fresh pyrite (15%). Also scattered arsenopyrite crystals which are mostly (collectively) leached and partly replaced by siderite. Separate (authigenic) siderite spheroids in vague lenticular-layers which may be relict beds, or disrupted veins contemporaneous with tectonised slate. Gold grains 2 µm to 50 µm occur (alone) in host rock, as inclusions in pyrite, rarely in and adjacent to siderite arsenopyrite.



Au 7359 ppb, As 7412 ppb



Extremely fine sericite-rich schist (or phyllite), incorporating numerous single euhedral crystals of pyrite, arsenopyrite > oxidised siderite, scattered and in loose clusters, also numerous voids.

Microscopic (part only)

Gold in this polished thin section has three different modes of occurrence. One occurrence of most concentrated gold is a cluster of about 25 grains of gold located within host rock sericite/decussate-fine muscovite, individual size range 1 µm to 50 µm, over an area about 0.1mm to 0.3mm, see photomicrographic Fig Nos.5 and 6. These gold grains are not directly associated with pyrite or arsenopyrite, but several equally small grains of a mineral semi-qualitatively identified by SEM tetrahedrite-tennantite [Cu3Sb-AsS3.5±Fe,Zn,Ag] occur in this cluster. Also the largest gold grain about 50 um size, has 2µm inclusions which SEM indicates as As>S, Ni and Fe. Gersdorffite as an approximate best-fit mineral (NiCoFe) AsS, but without Co reported in this particular analysis.

Gold also occurs as inclusions ranging in size from 1 micron through to 50 micron, within pyrite and rarely within altered arsenopyrite, see Fig Nos 5 to 12. Optically, the siderite replicas replacing arsenopyrite are seen to be very largely "opaque", apparently due to being crowded by carbonaeous "dust".


Fig 5
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Fig 6
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Fig 7
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Fig 8
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Fig 9
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Fig 10
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Hole CD06-2


One domain dominated by crystals of arsenopyrite > pyrite (including subordinate composites of these two sulphides), incorporating interstitial vein quartz and fragments of slate host rock. Second domain of coarse vein quartz with lesser clusters of sulphide intrusive into disrupted slate. Numerous grains of gold, 2µm to 75 µm size, almost invariably within pyrite (which is also composite with arsenopyrite, which is devoid of observed gold).

Au 11610 ppb, As 1500 ppm



This small piece of core, 40mm long, consists of a band about 20mm of concentrated subhedral to euhedral pyrite and arsenopyrite crystals, largely within slate. this forms an irregular contact against coarse vein quartz which carries local incursions of the above slate-sulphide material. Slickensides on separate pieces of slate indicate shearing.

Reflected light examination of the band with most abundant sulphide consists of a loose aggregate of arsenopyrite > pyrite crystals, overall size range 0.1mm to 4mm maximum dimension, semi-quantitatively represented as follows:
  • Single phase (monomineralic) arsenopyrite crystals - 50%
  • Single phase (monomineralic) pyrite crystals - 30%
  • Composite (contemporaneous) pyrite-arsenopyrite crystals, almost invariably with pyrite dominant over arsenopyrite - 20%

About 10% of this whole band consists of (non-sulphide) carbonaceous slate, carrying trains of arsenopyrite crystals. Another 20% of this whole band consists of fine vein quartz, intricately interstitial to the greater majority of loose-packed and randomly sized sulphide crystals.

The other part of this sample dominated by coarse hydrothermal quartz, carrying minor localised clusters of pyrite collectively > arsenopyrite, also minor incorporated fragments of slate.

Contact between the two domains is heterogeneous but the overall impression is that at least the majority of sulphides have been carried by the vein quartz, intrusive into a disrupted zone within the (carbonaceous) slate, largely incorporating fragments, depositing sulphides.

Numerous occurrences of gold in this polished thin section are best demonstrated in the series of photomicrographs, Fig Nos 34 to 38. About 40 individual grains of gold were seen, ranging in size from 2 micron to 75 µm, and all except one of these occur in about six crystals of pyrite, most of which are composite arsenopyrite. The one grain (5 µm size) occurs in arsenopyrite which is composite with pyrite carrying 8 gold particles 10 to 30 µm size.


Fig 36
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Fig 37
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