Earaheedy / Imbin is a VMS Deposit, page-3

The ores at DeGrussa are classified as volcanic hosted massive sulphide (VHMS) style deposits, occurring as massive lenses of primary pyrite, chalcopyrite and pyrrhotite with minor magnetite, sphalerite, galena and arsenopyrite in a gangue of siderite, ankerite, stilpnomelane, minnesotaite, quartz and calcite.

The primary mineralisation has been subjected to oxidation and supergene enrichment near surface to produce a surface zone with native copper and siliceous cap with gold, overlying a layer of oxide/carbonate copper and a blanket of supergene chalcocite with tenorite, cuprite and complex tellurides.

The main DeGrussa deposit represents a 20 m-thick, steeply dipping to almost vertical body of high grade copper-gold mineralisation with lesser zinc and silver that lies structurally above Conductor 1. It is defined over a 180 m lateral strike extent and persists to a known vertical depth of more than 300 m. It is bounded by chloritised lithic sedimentary and volcaniclastic rocks on the structural hanging wall side and mostly basaltic lavas, doleritic and **broic rocks on the structural footwall. The footwall **bro and dolerite are pervasively altered to an assemblage of epidote, Mg-rich chlorite, sericite, calcite, titanite (altered to leucoxene), albite and quartz, associated with a network of microfractures.