Assay results of copper ore samples taken from AQSE- and A2X-listed Marula Mining’s Kinusi copper mine, in Tanzania, have confirmed the high-grade copper content of the copper concentrates currently stockpiled and ready for sale.

The assay results, which were received following analyses completed by an independent and internationally accredited laboratory, reported an average grade across the three samples of 21.54% copper, and with individual assay results of 20.21%, 21.77% and 22.64% copper.

The assays were from three 10 kg copper ore samples that were taken from the Kinusi No 4 openpit in the fourth quarter of last year.

The samples were collected and assayed as part of the process to complete initial copper ore trial shipments and sales of up to an initial 1 000 t to Swiss- and UK-based global commodity trading groups.

With these assay results now received, and confirming the high-grade copper mineralisation of the stockpiled copper concentrate product specifications, these initial sales agreements can now be finalised, Marula said on January 31.

The company had previously announced that it expected these copper sales to be completed by January 31. However, this has been delayed. Marula said it is progressing these initial sales agreements following receipt of the copper assay results.

These assay results will also be used to optimise the design of both the Phase 1 and 2 processing plant at Kinusi. 

The two-phase development of Kinusi comprises of an initial Phase 1 gravity concentrate, coarse jigging and fines dewatering circuit expected to produce 24 000 t/y of high-grade copper concentrate.

The awarding and commissioning of the Phase 1 gravity concentrate, coarse jigging and fines dewatering circuit on site remains on schedule for completion in the first quarter. 

The second Phase 2 processing plant will then incorporate a hydrometallurgy fines optimised heap leaching circuit, a copper solvent extraction as well as electrowinning refining process to produce an initial 10 200 t/y of copper cathode.