RE:Swan and Eagle Zones at Fosterville When gold precipitates in a low temperature epithermal environment it precipitates alongside other low temperature epithermal minerals such as Stibnite (Sb), Boulangerite (Sb), Realgar (As), Orpiment (As), Cinnabar (Hg) and Adularia (K). These minerals are more abundant than the gold and can be considered pathfinders for the gold. Many are brightly coloured or otherwise distinctive.
Mineralization along the Appleton fault is considered to be low to mid temperature epithermal.