Porphyry Exploration & Development
Dart Mining’s key founding strategy upon listing in 2007 was to seek opportunities for porphyry-style mineralisation in NE Victoria. NE Victoria has a variety of prospective granitic plutons, which have been demonstrated by Dart Mining and others to contain Cu, Au, Ag, Zn, Li, Sn, Ta, Mo and W. Prospective porphyry-style mineralisation is interpreted to be located above a large strike swing in the Gilmore Suture and straddling an Arc – Back Arc setting which has imparted metallogenic signatures and mineralisation styles of both settings. The region is thought to be underlain by the Macquarie Arc, the host rocks of porphyry gold, gold/copper and copper porphyry mineralisation further north into NSW at mining centres around Cadia – Ridgeway and the Endeavour deposits. This is a highly prospective area and is recognised by the Geological Survey of Victoria as being one of two newly recognised Arc Belts within Victoria, the other being the Stavely Belt in western Victoria.
Dart Mining has made significant discoveries in altered, oxidised, fractionated, I-type intrusions at Unicorn (Cu-Mo-Ag) and Morgan. Previous explorers have also discovered polymetallic porphyry-style mineralisation in the region, including gold and silver at the Mammoth Porphyry some 70km south of Corryong.
Dart Mining’s exploration has also targeted zones of alteration within de-magnetised, oxidised plutons. This has resulted in the discovery of strong geochemical anomalies over demagnetised zones at the Gentle Annie and Staceys prospects (both within EL4726) that await drilling. Historic mining at Granite Flat-Empress (EL006277) focused on high-grade gold concentrated in shear zones within the Banimboola pluton. More recent exploration drilling has led to the identification (Potter, 1997) of two mineralising phases at Granite Flat, a broad low grade signature (potential porphyry style stockwork Au / Cu) overprinted by narrow, high grade zones. Much of the drilling shows broad intercepts of highly anomalous gold and coincident copper mineralisation.
Dart’s suite of identified porphyry projects includes:
· STACEY’S (Au, Cu)
o strong Au/As/Cu Geochem, mapped QF dykes
· GENTLE ANNIE (Cu, Au, Mo)
o mapped QFP, classic geochemical and geophysical porphyry signature
· EMPRESS (Au, Cu)
o Large Au-Cu footprint in historic workings – Cu+Au noted in porphyritic rocks
· MORGAN (Mo, Ag, Sn, Au)
o known mineralised Mo-Ag(+Au) QFP. Large classic porphyry geochemical signature
· COPPER QUARRY (Cu)
o outcropping altered and mineralised QFP, strong Cu soil geochemistry, bimodal system
· EMPRESS SOUTH (Cu)
o magnetic signature with strong Cu soil geochemistry
· UNICORN (Mo, Cu, Ag, Zn)
o 200Mt Mo-Ag-Cu resource in outcropping QFP. Climax-style mineralisation. Additional targets at depth and adjacent
· SHIPPEN GULLY PORPHYRY
o Multiphase intrusion, silica flooded with stockwork showing Mo