Precious and base metals project developer Ivanhoe Mines has intersected another high-grade strike of mineralisation at the Kamoa-Kakula project, in the Democratic Republic of Congo (DRC).

The company on Sunday said drilling at the Kamoa North Bonanza Zone deposit returned an estimated grade of 18% copper over 18.86 m at a 2% cutoff, beginning at down-hole depth of 209 m, making it the highest-grade intersection ever drilled at the project.

Ivanhoe warned in a release that the Niton X-ray fluorescence (XRF) readings of the intersection were not the same as laboratory assays and were not an estimate of resource grades; however, based on more than 1 570 holes drilled to date at Kamoa-Kakula, and the high degree of correlation between Niton XRF readings and assay results, the company was confident that these readings were highly useful in shaping the next stage of the delineation drilling programme.

The Kamoa North Bonzanza zone represents a new style of copper mineralisation at the project, where massive to semi-massive chalcopyrite, bornite and chalcocite have locally replaced pyrite in the Kamoa Pyritic Sultstone – a pyritic siltstone that lies immediately above the basal diamictite unit that typically hosts the copper mineralisation at Kamoa-Kakula.

Drilling has extended the strike length of the Kamoa North Bonanza zone to at least 550 m, with a width of up to 60 m across strike.

Six drill rigs are defining, or extending, the limits of the Kamoa North Bonanza zone, which has an implied strike length of 2.72 km.

Kamoa-Kakula project geology manager David Edwards commented that while the company looked forward to working toward an initial resource estimate for the Kamoa North Bonanza zone, it was also looking forward to leveraging the team’s proprietary exploration knowledge to search for the next bonanza-grade copper discovery on the Kamoa-Kakula mining licence and on the adjacent Ivanhoe-owned Western Foreland exploration licences.

The Kamoa-Kakula project is about 25 km west of the mining centre of Kolwezi in the DRC.

The project is 39.6%-owned by Ivanhoe, 39.6%-owned by Zijin Mining Group, 0.8%-owned by Crystal River Global and 20%-owned by the DRC government.