Renison is the largest of three major Skarn, carbonate replacement, pyrrhotite-cassiterite deposits within western Tasmania. The Renison Mine area is situated in the Dundas Trough, a province underlain by a thick sequence of Neoproterozoic Cambrian siliciclastic and volcaniclastic rocks. At Renison there are three shallow-dipping dolomite horizons which host replacement mineralisation.

Mount Bischoff is the second of three major Skarn, carbonate replacement, pyrrhotite cassiterite deposits within western Tasmania. The Mount Bischoff Mine area is situated within the Dundas Trough, a province underlain by a thick sequence of Neoproterozoic- Cambrian siliciclastic and volcaniclastic rocks. At Mount Bischoff folded and faulted shallow dipping dolomite horizons host replacement mineralisation with fluid interpreted to be sourced from the forceful emplacement of a granite ridge and associated porphyry intrusions associated with the Devonian Meredith Granite, which resulted in the complex brittle / ductile deformation of the host rocks. Lithologies outside the current mining area are almost exclusively metamorphosed siltstones. Major porphyry dykes and faults such as the Giblin and Queen provided the major focus for ascending hydrothermal fluids from a buried ridge of the Meredith Granite. Mineralisation has resulted in tin-rich sulphide replacement in the dolomite lodes, greisen and sulphide lodes in the porphyry and fault / vein lodes in the major faults. All lodes contain tin as cassiterite within sulphide mineralisation with some coarse cassiterite as veins throughout the lodes.

RENISON TIN OPERATIONS
The Renison Tin Mine (Renison) is located approximately 15km north-east of Zeehan on Tasmania’s west coast. Renison is a world-class, long life underground mining operation producing tin concentrate.

The Renison mine predominantly applies up-hole benching and open stoping mining methods with (in some cases), post fill and cemented rock fill to fill voids. The weighted average mining dilution is 14% at zero grade. Minimum widths for underground development are 4.5m and for stoping minimum widths are 2.2m.

RENISON TAILINGS RETREATMENT (RENTAILS) PROJECT
The objective of the Rentails Project is to re-process the estimated 22.5 Mt of tailings at an average grade of 0.44% tin and 0.23% copper from the historical processing of tin ore. The current tailings dams have a Mineral Resource containing approximately 104,000 tonnes of tin and 53,000 tonnes of copper (refer to ASX announcement dated 30 January 2020).

The underground mine operates a primary crushing system before the material is transported to the surface through a shaft. Once there, it enters the pre-concentration plant, where it undergoes a three-stage crushing, screening and cleaning process. The particles are split into two fractions – 10-25 mm and 25-60 mm – which are fed into two TOMRA XRT sorters. The output consists of two streams: the product, which is transferred to the wet plant, and the waste, which is fed into a TOMRA EM sorter to separate acid-forming sulphides from this waste stream.

In the wet plant, the product goes through primary grinding followed by bulk sulphide flotation. The tailings are processed downstream to concentrate the cassiterite tin mineral through gravity concentration; gravity tails are further treated via desliming and tin flotation. The combined concentrates are fed to a leaching circuit to remove carbonate minerals. After a final wash stage, the concentrate is de-watered and dispatche ........