Mining Magazine > Panorama > Rockwell x-ray technology for Saxendrift

Rockwell Diamonds’ board of directors has approved capital investment to install high throughput (or bulk) x-ray technology at its Saxendrift mine, one of its Middle Orange River properties in the Northern Cape province of South Africa.
High throughput x-ray plants are an advancement in diamond processing technology that concentrates and recovers diamonds in one single, cost effective and secure step. The technology can also identify rare Type II diamonds, which are known to be present in Rockwell’s Middle Orange River properties. Diamonds of this type are not generally recognised by the standard x-ray technology currently used at Saxendrift.
James Campbell, CEO of Rockwell, said: “The existing plant at Saxendrift is currently based on traditional pan plant technology that is known to be less efficient in the recovery of diamonds than the bulk x-ray technology which we are seeking to implement.
“We will pilot this technology at Saxendrift to fine tune it to our specific requirements. Our objective is to deploy the same technology over the next few years in the new processing plants that are planned to be built at Wouterspan and Niewejaarskraal with significant efficiency improvements over standard flow sheets.”
The project will include the procurement and installation of one high throughput Bourevestnik (BV) sorter and one BV single particle sorter for the concentration and final sorting of diamond-bearing ore at Saxendrift. The capital cost of US$1.5 million will be funded from the proceeds of the recent asset sales. This cost includes the installation of these units into an additional 400t/h plant at Saxendrift.
Evaluation of the new technology for Saxendrift suggests that the new installation is likely to achieve a positive payback after old recovery plant tailings are retreated. The new plant will be used to process the run of mine ore and is expected to result in a significant improvement in diamond recoveries.
Mr Campbell added: “Together with the other improvements currently in progress at Saxendrift and the recovery of high quality gem stones, we are confident that production at this mine will improve significantly to enable it to produce more of the large, high value diamonds for which it is known.”