Gemfields unveils new $15m automated ruby sort house in Mozambique

22nd February 2019

By: Tasneem Bulbulia

Senior Contributing Editor Online


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Gemfields on Friday unveiled a new ruby sort house near its Montepuez ruby mine (MRM), in Mozambique.

The gemstone miner noted in a statement that the sort house, in which it invested $15-million, was the first of its kind for the gemstone industry and would be on par with the best diamond sorting facilities in the world.

The facility will enable Gemfields to consistently deliver a greater volume and spectrum of responsibly sourced rubies to the global market.

The facility itself is expected to raise production levels considerably.

It works by using the natural properties of rubies as a means of automated sorting. The process starts with the washing of the raw material, before passing it under ultraviolet (UV) light.

Rubies naturally fluoresce under UV light, meaning optical sorters can detect the fluorescence and employ blasts of air to direct individual rubies to separate channels for further sorting and grading, Gemfields explained.

The use of programmable logic controllers and data software under the UV light to conduct this process is said to be faster, more reliable and more efficient than sorting by hand.

It also allows the identification of a finer material component than before. A greater number of washing plants – the equivalent of washing 10 000 t/d of ore – combined with UV optical sorting, account for how throughput will increase exponentially, translating into considerably higher production figures.

“Previously, the sorting of rubies was largely manual, but it is very exciting to now introduce automated sorting which will require minimal manual sorting,” commented ruby grading supervisor Kaung San.

“Our productive capacity will increase exponentially.”

However, the company reassured that the introduction of automation will not mean a reduction in workforce, but rather, will have the opposite effect.  

Firstly, the greater throughput of the sort house means an expansion of the current active mining area, which will require an increase in workforce.

Secondly, the manual part of the sorting process – categorisation and grading the rubies themselves – will require a greater volume of highly skilled employees.

Rather than importing this expertise, MRM is creating the first group of Mozambican gemmologists specialised in the selection and classification of rubies, which it enthused marks a “substantial” step for the ruby industry.

Notably, the installation of the technology itself has equipped the Mozambican workforce with the technical ability to understand, operate and manage facilities of this nature anywhere in the world, enabling their place as a specialised and competitive labour force in the international employment market.

“We believe this new machinery will enrich and expand the knowledge of our employees, creating development opportunities and specialisation in the field of gemmology within the local workforce,” said ruby sort house head Mervyn Dettmer.

The investment in this project is one of the largest investments of its kind in the Cabo Delgado province.

It represents MRM’s commitment, as a Mozambique-based company, to continue to contribute to the development of the province, the Montepuez district, the local communities and the country, the company enthused.  

The sort house is expected to engender improved productivity, more efficient production, a reduced margin of error and, in the medium to long term, a reduction in production costs.

The increase in production and expansion in workforce not only benefit the local communities, but also generate a greater contribution to the national economy through taxes.

This means a greater positive impact for the people of Mozambique, a core value of Gemfields’ operations.

This year will be a significant year of investment and growth for Gemfields’ Montepuez ruby mine, as the new sort house will be complemented by the implementation of a new thickener to the wash plant, increasing capacity to 150 t/h, from the current 125 t/h.

Two high-capacity pre-screen plants will be brought online to remove the finer particle material prior to it being fed to the wash plant, which will result in a greater concentration of the desired size material, further enhancing the wash plant feed capacity.

Edited by Chanel de Bruyn
Creamer Media Senior Deputy Editor Online



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