JSE- and ASX-listed Orion Minerals has successfully completed confirmation drilling at Okiep in the Northern Cape, with results confirming the high quality of a large historical drilling database inherited from Newmont and Gold Fields, the company said on September 3.

Assay results received for confirmation diamond drill holes completed at Flat Mine North and the last two confirmation diamond drill holes completed at Flat Mine South include significant intersections.

Drill hole OFMSD079 intersected 14.8 m at 2.58% copper within 25 m at 1.92% copper, while drill hole OFMND243 intersected 36.3 m at 1.11% copper. Both Flat Mine North and Flat Mine South will form a key part of Orion’s early production plan for the Okiep copper project.

Orion said that the intersections achieved to date support geological and grade distribution interpretations that were incorporated in the mineral resource estimation for the project.

Drilling is continuing at Flat Mine South to test the down-dip extension of high-grade mineralisation in a previously untested area. Confirmatory drilling has been completed at Flat Mine Nababeep, where an inferred mineral resource of one-million tonnes at 1.4% copper was reported in March 2021. Latest assays include drill hole OFMD164, which intersected 20.69 m at 1.82% copper within 45.69 m at 1.26% copper, drill hole OFMD167, which intersected 7.8 m at 5.08% copper, and drill hole OFMD169, which intersected 21 m at 1.83% copper.

Orion said that the completion of the confirmation drilling programme within the Flat Mines Area represents an important final input for the completion of the bankable feasibility study (BFS) for the Okiep early production plan, with this study on track for delivery in the coming weeks.

"The drilling programme that we have now completed confirms our best expectations regarding the quality and reliability of the historical drilling data from the Okiep copper project," Orion MD and CEO Errol Smart said.

He highlighted that previous owners Newmont and Gold Fields, which milled more than 77-million tonnes of high-quality sulphide copper ore from Orion’s current prospecting and mining rights, relied on the high-quality work undertaken by their highly acclaimed geology department and laboratories.

"In its time, the Okiep laboratory was the go-to laboratory for assay checking and quality control for the entire Southern African region," Smart said.

Smart emphasised the importance of the Flat Mines project, now fully permitted for mining, and noted that the secured surrounding prospecting rights and high-quality drilling data were expected to provide a pathway for Orion to fast-track the expansion of the initial production profile and mine life outlined in the initial BFS.

"We are tremendously excited about the future of the Okiep copper project, which is proving itself to be a world-class, build-ready copper mine," Smart said.

The latest results add momentum to Orion’s development strategy for the Okiep copper project, building on initial results reported earlier this year. The project ground holdings of 703 km² cover most of the copper mining district, where a total of 105-million tonnes has been reported to have been mined over the past 100 years. Of this, about 77-million tonnes were mined on the Okiep copper project’s prospecting and mining rights.

The Flat Mines Area and the current drilling programme fall entirely within executed mining right NC10150MR, which is surrounded by the newly granted prospecting rights NC12755PR and NC12848PR.

These areas host several historically drilled prospects and historical mines that offer the potential for additional mineral resources through future drilling. The assay results have confirmed historical information from drilling by Newmont and Gold Fields in the 1980s and 1990s, which underpinned Orion’s updated mineral resource for the Flat Mines deposits of 9.3-million tonnes at 1.3% copper.