Scheelite skarn mineralisation has formed within the metamorphic aureole of the Carboniferous Grassy Granite where it is in proximity to the calcareous sediments and carbonates of the Lower Grassy Group. The Dolphin and Bold Head deposits are hosted in a similar stratigraphic sequence.

Mineralisation is hosted within a 100-200m thick sequence of complex skarn mineralogy with two main horizons known as B and C Lens both of 10-30m thickness separated by a similar thickness of skarn altered volcanic sediments. Skarn formation and mineralisation have occurred where carbonates come into direct contact with the intrusion, or adjacent to brittle faults intersecting the intrusion. Mineralisation in the Dolphin deposit is best developed within C Lens which has several distinct mineralogical components including a garnet hornfels, a pyroxene-garnet hornfels and banded pyroxene garnet hornfels. B Lens is an upper dolomite horizon which has been variably hornfelsed and metasomatised with sporadic mineralised pyroxene-garnet skarn.

The Dolphin deposit dips east to southeast at approximately 30° before steepening to 50° in proximity of the Decline Fault on the eastern margin of the deposit. The host stratigraphy is broadly folded by several southeast dipping open anticlines or vergence folds with wavelengths of a few tens of metres. Several major southeast and east trending normal faults associated with the folding cut the orebody into discreet fault blocks. The North ........

The OC mine is proposed to be an own-operate, truck-shovel operation utilising mid-sized hydraulic excavators matched to a fleet of 75 tonne dump trucks The UG mine will be decline accessed and based on contract mining for development and ore production using standard rubber tyred diesel and electro-hydraulic underground mining equipment.

Open Cut Mining
Updates to the 2019 Mineral Reserve Estimate have been made during the current Feasibility Study, none of which are considered to result in a material variance from the original estimate of 3.0Mt @ 0.73% WO3. Technical studies into scheduling, equipment, drill and blast and power and fuel costs have resulted in minor revisions to cost estimation. Physical constraints, cut offs and mine design remain essentially the same with the most significant updates to the 2019 estimate being:
- Updated equipment list;
- Revision of ore schedule into 2 stages;
- Smoothing of the waste movement schedule to optimise mining costs;
- Increased drilling capacity with smaller holes and 100% emulsion explosives to reduce blasting effects on Grassy town and improve fragmentation;
- Updated OC cost estimation.

The majority of the waste and ore will require drill and blasting; the exception to this being old fill and marine sand material. Blasts will be engineered to ensure minimum displacement of the ore to minimise dilution and ore loss. Drilling will be carried out by 2 top hammer rigs with b ........

Significant modifications to the process flowsheet and plant design since the 2019 FS (ASX:KIS 3 June 2019) have been made, mainly to the gravity circuit resulting in a reduced flotation requirement. Civil construction associated with processing outside of the Gekko scope was designed and costed by BR Design. The process flowsheet design includes two stage crushing, using jaw and cone crushers, fine ore stockpile, fine vertical shaft impact crushing, coarse and fine gravity concentration using spirals and tables, dressing of gravity concentrates by flotation and magnetic separation and finally drying, blending and bagging of concentrate. Plant throughput is expected to average 60 tonnes per hour.