The world’s largest high grade, copper-only deposit, situated in the DRC – Kamoa-Kakula – will join the elites of copper mine producers across the globe when it transitions from development into production.
While the two mines represent an excellent starting point for developer and joint venture owner Ivanhoe Mines, ongoing exploration in close proximity to the ore bodies is revealing greater potential for expansion with similarly high grades.
Laura Cornish visited the project in June 2018 as part a small group of delegates, hosted by Ivanhoe Mines, as part of the annual DRC Mining Week 2018 conference and exhibition held in Lubumbashi.
Kamoa-Kakula is a mining celebration for many reasons, which in addition to its status as the world’s largest high copper deposit, represents the commitment one mining company (and its partners) has been to delivering economic wealth to the Democratic Republic of Congo (DRC) and Africa at large through its billion-dollar investment in building new Greenfield copper mines in the country.
The tier-one Kamoa-Kakula project is a joint venture between Ivanhoe Mines, China’s Zijin Mining and the DRC government.
This article first appeared in Mining Review Africa Issue 8 2018
Today, the project consists of two large-scale underground developments.
Kamoa’s Kansoko mine decline is complete and the adjacent Kakula decline is advancing with rapid speed.
But reaching this point has been no small feat. Exploration on the 400 km² licence area began in 2003 – a decade and a half ago.
The drilling programmes that followed were extensive, especially after the Kakula ore body was discovered early in 2016, eight years after Kamoa.
A visit to the Kamoa site reveals hundreds of thousands of metres of core drilling – totalling over 450 000 m as of the end of February 2018.
It also showcases Ivanhoe’s commitment to positioning itself as long-term partner to deliver economic upliftment in the region, with benefits extending from nearby local communities all the way to Kolwezi, the closest major town, about 25 km away.
Kakula’s star shines brightly
If Ivanhoe Mines had only ever discovered the Kamoa deposit it would have secured itself a rich copper mining future.
The project alone boasts impressive economics.
Today however, it represents just one component for the overall project thanks to Kakula, which boasts even better mineralisation, reef thickness and reef continuity. It is located just 10 km south-west of Kamoa’s Kansoko mine.
The Kakula mineral resource estimate (updated in February this year) covers a mineralised strike length of 13.3 km and incorporates the newly discovered Kakula West discovery area and the saddle area between the two ore bodies.
The Kakula high-grade mineralised trend also remains open in multiple directions says Teddy Bin Njojo, the deputy site and operations manager for Kamoa Copper SA (Ivanhoe’s local subsidiary), who was part of the Ivanhoe team conducting the site visit.
The new estimate boosts the total tonnage of Kakula’s indicated mineral resources by 50%, at a 3% copper cut-off, compared to the previous Kakula resource estimate issued in May 2017 that covered a strike length of 7.7 km.
Kakula’s new indicated mineral resources at a 3% cut-off grade have increased by 58 Mt and currently totals 174 Mt at a grade of 5.62% copper.
This compares to the May 2017 estimate of 116 Mt at 6.09% copper, at the same cut-off grade. Estimated inferred mineral resources now total an additional 9 Mt at a grade of 3.66% copper, at a 3% cut-off.
At a 1% copper cut-off, Kakula’s indicated mineral resources have increased by 58%, to now total 585 Mt at 2.92% copper.
Njojo reveals that the underground development work on the twin declines at Kakula, a conveyor decline and a service decline for personnel and equipment, is progressing well. “We anticipate reaching reef by the end of December this year at approximately 1 400 m,” he confirms.
In June, both declines were approaching the 600 m halfway mark.
This will be a significant achievement considering the Kakula box cut was completed less than a year ago in October 2017, followed by the first blast for the twin declines at Kakula in November.
The decline development work is being undertaken by JMMC, a DRC subsidiary of JCHX Mining Management of Beijing, China.
Initial mine development is planned to begin at the Kakula deposit in a flat, near-surface zone along the deposit’s axis that, at a 3% cut-off, is between 7.1 m and 11.7 m thick, with copper grades of between 8.11% and 10.35%.
Based on the findings of the independent preliminary economic assessment completed in November last year, Kakula’s copper grade is projected to average 6.4% over the first 10 years of production.
Briefly turning to the Kansoko development, Njojo reveals that the mine’s twin declines, 1 000 m in length, intersected reef in August 2017.
“It was completed on time and on budget and is operationally read to start producing. Subsequent to this, we have stockpiled 13 000 t of copper material from the mine which can be used to test run our process plant as we build momentum towards production start-up.”
Because of Kakula’s economics, the priority is completing underground development in build-up to production. This mine will come on stream first.
Options on how to bring the Kansoko mine on-stream are currently being considered.
“Production options for Kamoa-Kakula include an initial 6 Mtpa ROM operation at Kakula, mining ore at a grade of 7.3% and producing 385 000 tpa of copper in concentrate by year four.
The alternative is to bring Kakula and Kansoko on stream together or Kansoko after Kakula. Another 6 Mtpa ROM from Kansoko at 245 000 tpa of copper in concentrate by year 7 and, combined with Kakula, would deliver production of 542 000 tpa of copper in concentrate in year 9 of operations from the two mines,” Njojo outlines.
The plant will be modular in design to accommodate easier expansions as required. “This will position us as the fourth largest copper producer in the world.”
The process plant will use conventional crushing and milling methodologies, followed by primary and secondary flotation to produce a copper concentrate.
Studies indicate that recoveries will be about 86% and the copper grade in concentrate at Kakula is 55% – significantly higher than ‘typical’ copper producers in neighbouring Zambia.
A smelter is also in the pipeline and will likely be considered about two years after the process plant has been operating.
Regional copper wealth in abundance
“We’ve only explored about half of our concession,” says Ivanhoe Mines’ DRC operations MD Louis Watum.
And even though the company ‘has its hands full’ with Kakula and Kansoko, it is engaging actively in exploration work to further determine the greater potential within its licence area.
The western trend of Kakula’s high-grade mineralised core appears to be open to the south-west, suggesting that potential extensions of the Kakula West discovery could remain within the Kamoa-Kakula mining licence for a considerable distance.
The ongoing gravity and geophysical seismic surveys will provide Ivanhoe Mines’ geological team with additional data to better assess the direction and extent of Kakula’s high-grade mineralised zone.
Kakula alone is significant enough in size to be developed as another standalone mine.
“What this ultimately equates to is well beyond 100 years of operating lifespan,” Watum concludes, summing up the bottom line of what is destined to be one of the wealthiest copper regions on the planet.