HomeDiamonds & GemstonesGravelotte emeralds to undergo commercial pricing assessment

Gravelotte emeralds to undergo commercial pricing assessment

ASX-listed Magnum Mining & Exploration is under way with the recovery of a parcel of emeralds from the trial mining programme at its 74%-owned project.

South Africa – The current processing of the mined material has been designed to recover a parcel of emeralds from Gravelotte of a sufficient size to allow a commercial assessment of pricing for the emeralds through a tender process.

The company said that there has been a significant increase in demand for emeralds reported since 2000 so this will provide vital data for assessing the current demand and consequent pricing for emerald product from Gravelotte. It in turn will allow the financial modelling for a potential future commercial mining operation to be completed.

The significant mining and exploration data base at Gravelotte has allowed Magnum to fast track the evaluation of the project for the potential near-term establishment of a modern emerald mining and production operation.

The final key steps in this evaluation programme have been to undertake testing to determine the best crushing, washing and processing techniques for the Magnum material and then utilise this information in a trial mining exercise utilising the existing historic open pits.

The first part of this programme was completed in 2018 and Magnum now has a strong understanding of the crushing and beneficiation characteristics of the Gravelotte emerald bearing rocks.

The second part of the programme – the mining of hard rock from the Cobra and Discovery historic pits, commenced in March 2019 and to date around 7 500 t has been stockpiled from the Cobra pits.

An estimated 2 000 t remains to be trucked and stockpiled from the Discovery pit.

Magnum has had a crushing and washing plant capable of processing around 2 000 tpm constructed on site and the commissioning of this plant was completed earlier in May, utilising low grade and waste material from the historic mining operations.

Processing of the Cobra mined material through this plant has now commenced and the product stockpiled for the secondary processing by XRF sorting.

The XRF unit is now on site and is undergoing calibration prior to the commencement of the secondary processing. This calibration is scheduled to be completed in the first week of June 2019. Based on a conservative base case it is targeted for around 250 000 carats of emeralds to be produced from the mined material.

Magnum Mining & Exploration anticipates that the definitive financial modelling will commence in the December 2019 quarter.