Picture shows delivery of a new jumbo drill rig to be used to expedite underground development work at Ivanhoe Mines’ Kakula deposit in the DRC. Initial mine development is planned to begin at the deposit in a flat, near-surface zone along the deposit’s axis that is between 7.1 and 11.7 m thick, at a 3% cutoff, with Cu grades of between 8.11% and 10.35%.
In February, the company reported an independently verified, updated Mineral Resource estimate for the ultra-high-grade Kakula discovery on the Kamoa-Kakula copper project, near the mining centre of Kolwezi.
The tier-one Kamoa-Kakula project is a joint venture between Ivanhoe Mines, Zijin Mining and the government of the DRC.
The updated Kakula Mineral Resource estimate, prepared under the direction of Amec Foster Wheeler, covers a mineralized strike length of 13.3 km. For the first time, the updated estimate incorporates Mineral Resources contained in the Kakula West discovery area and the saddle area between the main Kakula discovery area and Kakula West.
The new estimate boosts the total tonnage of Kakula’s Indicated Mineral Resources by 50%, at a 3% Cu cutoff, 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% cutoff grade have increased by 58 Mt and currently total 174 Mt at a grade of 5.62% Cu. This compares to the May 2017 estimate of 116 Mt at 6.09% Cu, at the same cutoff grade. Estimated Inferred Mineral Resources now total an additional 9 Mt at a grade of 3.66% Cu, at a 3% cutoff.
At a 1% Cu cutoff, Kakula’s Indicated Mineral Resources have increased by 58%, to now total 585 Mt at 2.92% Cu.
The Kakula high-grade mineralized trend remains open in multiple directions. Robert Friedland, Executive Chairman, said Ivanhoe expects that ongoing in-fill and step-out drilling will yield significant expansions and further upgrades to the current resources.
“Kakula is the most remarkable mineral discovery we have seen during our 35-plus years in the exploration industry. The new, independently-verified resource estimate now places Kamoa-Kakula ahead of Indonesia’s renowned Grasberg deposit as the world’s fourth-largest copper discovery on the planet in terms of contained copper. And it still is growing.
“The exceptionally high copper grades, thicknesses and continuity of the mineralization at Kakula distinguish this discovery from anything else in the Central African Copperbelt,” Friedland added.
“Based on the findings of the independent preliminary economic assessment completed in November of last year, the resources we’ve discovered should allow us to build a world-scale, highly-mechanized, underground copper mine with an initial capital cost expected to be far lower than other operations of this size.
“With this initial Mineral Resource estimate at Kakula West, we can begin to evaluate technical and infrastructure options to expeditiously develop the zones of thick, high-grade, bottom-loaded chalcocite in this latest discovery area.”
Friedland said that a development scenario using a mining rate of 6 Mt/y and a Cu cutoff grade of 3% indicates that Kakula already has enough Indicated Mineral Resources to mine at an average grade of between 5.5% and 6% copper for approximately 30 years.
“If we lower the copper cut-off grade to 1%, which is higher than the mining grades at most of the world’s major copper mines, we could be mining almost 3% copper at Kakula for approximately 100 years,” Friedland said.
“Importantly, the western trend of Kakula’s high-grade mineralized core appears to be open to the southwest, 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 our geological team with additional data to better assess the direction and extent of Kakula’s high-grade mineralized zone.
“The unparalleled strength and continuity of the Kakula mineralized trend also bodes well for the potential for exploration success on Ivanhoe’s 100%-owned Western Foreland licences, to the west of Kamoa-Kakula. Given the accumulation of in-depth, proprietary geological insights gained by Ivanhoe’s geological team into the features controlling the high-grade copper mineralization during almost two decades of exploring in the region, we are highly confident of further exploration successes in 2018 and beyond.”
The Kakula Discovery is approximately 10 km southwest of Kamoa’s initial Kansoko mine development. Ivanhoe and Zijin have been conducting an aggressive drilling program totalling more than 181,500 m at Kakula since April 2016. The program is expected to continue through 2018.
