Gold-silver mineralised veins at Favona, represent a new low-sulfidation epithermal vein discovery that occurs less than 1 km southeast of the world-class Waihi deposit. The Favona vein is hosted in Late Miocene andesitic lava flows and local dacitic tuffs that are intensely altered to quartz, adularia, chlorite, illite or interstratified illite-smectite (with ten to 70 per cent smectite) and pyrite. Adularia is widespread and envelops the veins, whereas chlorite and illite are mostly restricted to the footwall, and illite-smectite is confined to the hanging wall of the Favona vein. At shallow levels, kaolinite, cristobalite and rare alunite overprint the above minerals. A polymict hydrothermal breccia also occurs above and in the hanging wall of the Favona vein and contains clasts of altered andesite and various quartz vein fragments. Fluid inclusions in quartz veins sampled over a 300 m vertical interval have a homogenisation temperature range of 175 to 266C and dilute apparent salinities of <1.0 weight percent nacl equivalent. this overlaps with the temperatures inferred from clay minerals with illite having formed at>220C and grading into illite-smectite and local smectite which formed at <220 and><150c, respectively. the assemblage of quartz, adularia, chlorite, illite, illite-smectite and pyrite formed from upwelling alkali chloride waters, with the lack of calcite further inferring low concentrations of aqueous co2. in contrast, late kaolinite, cristobalite and alunite formed from descending steam-heated acid-sulfate waters. overall, the favona and waihi deposits are interpreted to have formed at similar levels in a single low relief hydrothermal system, with each deposit representing a distinct zone of fluid upflow.>