Ann: Investor Presentation - Resource Rising Stars Summer Series, page-14

Gateway’s project area has a history of gold production from a handful of shallow open cuts back in the 1980s and 1990s.And since then, there hasn’t been much in the way of exploration for high-grade extensions of both oxide and primary mineralisation at depth and along strike.The lack of exploration since the 1990s is a bit hard to understand given the width and high-grade intersections recorded in the bottom of the pits and off to the side, though there is an off-the-mark perception that region is dogged by refractory ores.

This is what I could find about refractory gold at Gidgee, taken from this article: https://www.resourcesrisingstars.com.au/news-article/dormant-gateway-set-rejuvenation-gidgee-gold-exploration-campaign