Mineralization is hosted in the Triassic Star Peak Group, a 1,220 metres thick section of marine platform limestone with lesser conglomerate, sandstone, and dolostone (Johnston 2008). Four formations comprise the Star Peak Group. In ascending order they are: the Dixie Valley, Favret, Augusta Mountain, and Cane Spring Formations. Most of the historic production came from the Augusta Mountain Formation.
Recent exploration drilling by Premier has led to discovery of the Carlin-Style CSD Gap Zone in 2016 and the polymetallic 2201 Zone in 2013. The CSD Gap is a high grade Carlin-Style deposit hosted within the same carbonate host rocks as the Helen and CSD deposits along the Cove trend. The CSD Gap discovery was a significant contributor of ounces to the 2017 Resource Estimate released by Premier and will be included in the ongoing preliminary economic assessment for the property. The 2201 zone is hosted within the Dixie Valley conglomerate beneath the Cove pit and is similar to the polymetallic sheeted sulfide veins that historically produced both gold and silver from the Cove pit. The gold and silver within the 2201 Zone is hosted as both stratabound and steeply dipping high-grade polymetallic sheeted sulfide veins that appear to be smaller imbricate reverse faults refracting upward from the Cove thrust. Due to the deep nature of the 2201 deposit it has seen limited drilling in recent years but has excellent potential for future expansion as the underground test mining project progresses.
A trident of known deposit types exist on the property, including skarn, polymetallic sulfides, and distal Carlin-style opportunities.