Coloured-gemstone mining operations especially artisanal mining have long been considered the least visible part in the whole gemstone supply chain from mine to market. A world leading supplier of responsibly-sourced coloured gemstones, Gemfields has committed to bringing visibility to the coloured-gemstone industry. Over the years, it has created a new vision for the sector by championing three key values – legitimacy, transparency and integrity throughout their operations.
In late May 2018, Hong Kong Jewellery was invited by Gemfields to visit its Kagem emerald mine in Zambia, experience and witness how they source emeralds – one of ‘the big three’ coloured gemstones and how they fulfil those values in a three-day tour.
The largest emerald mine
Zambia, a landlocked country in Southern Africa, is famous for its metal and gemstone resources. We first arrived at Ndola, the second largest city of Copperbelt Province in central Zambia where rich copper resources are found. After a two-hour drive passing through the highway and gravel road, we entered into the Kagem mine site which lies in Ndola Rural Emerald Restricted Area. Established by the government to wipe-out illegal mining, this restricted zone only allows government-authorised mining activities by large-scale companies and local miners.
Gemfields acquired the Kagem mine in November 2007 with a 75-percent share and the rest by the government of Zambia. The mine, controlled and managed by Gemfields’ Kagem Mining Limited, is the world’s largest emerald source which spreads over an area of over 40 square kilometres in the prolific emerald belt, and supplies more than 25 percent of the global emerald production.
Sean Gilbertson, CEO of Gemfields, told Hong Kong Jewellery that Kagem recovers an average of 2.5 million carats of emeralds and beryl per month, thirty million carats per year. Expectations for 2018 are in the region of 32 million carats, with an investment of approximately US$14 million in mine development. Kagem’s emeralds and beryl sold at Gemfields auctions have generated US$506 million in revenue since July 2009. The Zambian government’s share of these revenues exceeds US$105 million or 21 percent of the revenue.
After more than a decade of open-pit mining, according to SRK Consulting’s studies, Kagem is projected to operate for at least another 22 years, with proved and probable ore reserves (emerald and beryl) of 1.1 billion carats. “Right now, we have enough resources to operate open-pit mining which is easier and more economic than underground mining. Basically, I would say for Kagem the next 25 years will be very much safe, and we will consistently supply emeralds to the global market,” said Prahalad Kumar Singh, general manager of Kagem Mining Limited.
The actual process
On the first two days of our stay at Kagem, we experienced the whole process of mining including blasting, open-pit mining, washing, sorting and grading accompanied by Kagem’s management team. It was this first-hand experience that reveals how a well-organised mine works and how rare the gemstone is.
Gemfields uses strip-and-fill method to mine emeralds at Kagem. Specifically, at the 128-meter-deep main pit called Chama, mining operations mainly include waste stripping and ore mining. After blasting, excavators strip and remove wastes to open up the contact zone where ores (emeralds and beryl) may contain. “To reach 20 meters of ore, we have to strip 100 meters of waste. The average stripping ratio for Kagem is 1:90,” explained Singh.
Then, a team of workers carrying chisels go to the zone to recover exposed ores or, in rare cases, exposed emerald crystals by using the hand tool. During our tour at Chama, after the workers chiselled and removed the black mica schist from some ores, multiple high-quality emerald crystals were exposed. High-level roughs like these would be sent to the sorting house directly, while large rocks, which probably contain ores, would be loaded into trucks and then sent to the washing plant first to screen and sort. All emerald-bearing ores are finally sent to the sorting house for sorting and grading.
According to Singh, Gemfields runs four pits at Kagem right now, and handles 30,000 tonnes of rock per day. However, the ore recovery varies from nil to few tonnes and kilograms. Since the inception of operations, eighty-nine million tonnes of rock have been handled till end of May 2018. “A hundred tonnes of rock on average are likely to generate 60 grams of gemstones (emeralds and beryl). Among the total gemstone production, twenty-six percent is emerald whereas 73.5 percent is beryl. Among all mined emeralds, one to two percent is high grade, and only 0.5 percent is premium,” Singh noted.
Environmental concern
The first day at Kagem ended with a viewing of blasting. While the blasting was grand to look at, it aroused our concern over the impact of mining activities on the local environment. In a video interview with Hong Kong Jewellery, sustainability manager of Gemfields Jack Cunningham said the impacts of artisanal mining can be much more significant than the large mining operations at Kagem, because artisanal mining is with less control, less planning, less analysis and is hence unable to reduce its impacts on the environment. For Gemfields, they develop the mine with the mine plan, alongside the environment management plan which demonstrates how they minimise mining operation’s impacts on the local environment through many ways.
How Gemfields dumps waste rocks reflects its practice of sustainability. While many mining companies dump waste rocks that bear no ore with no commercial value in dedicated dump sites, Gemfields dumps them in other parts of the mine that are exhausted. This process is known as “back filling”. “It is more economically viable for us to back fill whilst we are mining than it is to dump the top waste elsewhere then back-fill in the future,” stated Cunningham. When the mining operations are done, they would put the topsoil or the waste rocks back to the mining area and then grow plants. “We retain the topsoil which enables us to grow sapling in the nursery and therefore replant native vegetation in the waste area or in the dump site on that area that has been back-filled,” he added.
In addition, Gemfields collects underground water in ponds so that they can extract that water for different uses like suppressing the dust in the area of the mine, watering plant, exposing gemstones in the washing plant and helping rip down the rock from gemstones. Also, they do not use any chemicals at any stage of the operations aside from diesel oil which are managed and disposed securely.
Shaping the future
Gemfields’ mining operation at Kagem has contributed to national economy of Zambia. As an advocator of corporate social responsibility, the company also aims at modernising the coloured gemstone sector and building lasting, sustainable livelihoods for the communities around the mine.
According to the company, since it began operation at Kagem, the mine has continuously added employment growing from 392 employees in 2008 to 923 in 2017. Since 2012, Kagem has invested US$2 million directly into the community, focusing on education, health and agricultural livelihoods. This includes the establishment of three schools, creation of two farming associations and the upgrade of a rural health facility to become a health centre. They have also shifted in helping members of the community set up their own businesses so that they can generate their own income independently off the mining operation.
“We form a strong partnership with the community where we mine gemstones,” stated Cunningham. He said that Gemfields cares more about what the community needs, and they know the money they invest will go further to benefit the local people in the long term. “We think this is very important because when we leave, they need to be self-sustained, they can’t just rely on the mine,” he said.
Joined Gemfields four years ago, Jack Cunningham described the company’s sustainable development over the years at Kagem as a “continuous improvement”. He concludes: “With anything related to sustainability there is more that can be done, more projects that can be undertaken, more areas that can be improved upon, and more processes that can be changed.”
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