Gemfields
The commissioning of the upgraded ruby processing plant at ASX-listed Mustang Resources’ Montepuez project in Mozambique has been highly successful.

MozambiqueMustang Resources reports that processing rates are now ramping up and given this excellent progress, it is confident that it will achieve its targeted processing rate of 1 500 tpd within weeks.

During the commissioning process, it was found that a much bigger recycling dam was needed to ensure sustainable water supply for the plant. The water is required to break and wash the clay out of the gravel. The new water recycling dam and plant will be in operation within a fortnight, which will allow the plant to work at full capacity.

The increasing throughput means that Mustang Resources is also on track to achieve its target of building a ruby inventory of 200 000 carats ahead of its planned initial auction in October this year. This will provide an opportunity to increase the volume of rubies available for sale in the October auction.

The upgraded plant is designed to achieve a feed/throughput rate of 250 tph and the company intends to initially operate the plant for one seven-hour shift a day.

This would enable the company to achieve or exceed its daily total processing target, which represents a 580 % increase in the throughput rates recorded before the US$1 million plant upgrade was undertaken.

It also means there is scope for further substantial increases in processing rates by operating additional shifts in the future.

Moreover, the upgrades to the plant are expected to increase the recovered grades. It is thought that many rubies were not extracted from the clay boulders and the conveyor belts to which they stuck. The conveyor belts were therefore replaced by wet jet pumps and the new larger scrubber has big water jets which break-up all clay boulders and send very clean gravels and stones to the pans.

Mustang Resources has now accumulated a 25 000 t stockpile at the Montepuez project sourced from three different pits on Licence 4143L.

It also expects to start bulk sampling on its recently acquired Licence 8245L, in which it has a 65% stake, within weeks.

Given the number of artisanal miners operating in this area, which indicate high prospectivity for rubies, and the shallow and high-grade nature of the deposits, this licence will be a key area of focus in coming months.