Runruno project resides within the Caraballo district, whose geology largely consists of pre Cretaceous to Early Cretaceous basement rocks consisting of ophiolite and schist underlying Late Cretaceous to mid-Miocene age volcanics, volcanoclastics and sedimentary rocks. The strata are intruded by the Upper Miocene Palali – Cordon Complex which is overlaid by Pleistocene lava flows, pyroclastics, marine sediment and Pliocene Matuno Formation.

Structurally speaking, the region is largely cut north south and moderate to shallowly dipping extensional structures. The area also has NW-trending, steep crosscutting arc-parallel faults which are interpreted as strike slip features. The area has undergone intrusion and uplift subsequent to and during the formation of the Palali-Cordon Alkali Intrusive Complex and is interpreted as an intra-arc basin.

Runruno sits at the intersection of the borders of two district-scale calderas, major NW and NE fault lines and a number of small volume, late composite volcanic centres. Mineralization at Runruno is hosted by a shallow-dipping fault zone of potassically-altered sericitized and brecciated tuffs and andesites which have been variably pyritized and silicified. Gold mineralization is preferentially hosted within fractures, faults, and breccias.

The style of gold mineralisation in Runruno is mostly as fine disseminations associated with pyrite and/or molybdenite. The original of the mineralisation is believed to ........

Runruno is a conventional drill and blast open pit mining operation. The space available for waste dumps in the mine is constrained by the short strike length of the orebody and steep terrain. Consequently, the waste material from the pit is currently placed in ex-pit dumps, with the pit being developed to accommodate in-pit dumping to progressively fill the mining void. The open pit area is 600 metres x 1,500 metres, with mining taking place in stages longitudinally along the ore body to provide an average strip ratio and consistent ore delivery to the plant.

Mining improvements
A number of improvements were made with respect to operating the Runruno open pit, which ensured the pit can operate smoothly until the end of mine life. The Runruno pit runs through Malilibeg Fault, however prior to 2019, there were no considerations for the fault in the mine design, which resulted in a number of unexpected pit failures starting in 2018, which effected the mining rates at Runruno. The new management redesigned the pit to put in a cutback, to satisfy the required factor of safety for the pit walls.

In addition, the original mine design had major issues with the design of the mine access. As previously mentioned all the mined waste gets placed back in the Runruno pit and thus pit design is staged, where material from a following stage is place back into the pit viod created from the previous stages. Previous design didn’t properly plan access ramps from one ........

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