Lulo and Catoca are located on the same geological belt, the Lucapa Graben. Lulo is located within 150km of Catoca, the world’s fourth biggest kimberlite diamond mine, and on the same favourable geological trend (Lucapa Graben).

Lulo hosts 296 kimberlite targets in two separate provinces, of which 96 have been classified as proven and probable kimberlites and four confirmed as diamond-bearing pipes.

Gravel horizon varies from 0.2m to 1.5m in thickness. Gravels are generally small with no large boulders. They appear to come from a low energy environment. Plenty of clays are still with the gravels but these are probably from decomposition in situ.

There are 50 km of river terraces that host gravels (full length of the Cacuilo river on the mining lease). At the rate of 20,000 BCM/month, the current identified resource estimate in a small part of the lease area has a life of three years, so resource definition of extended gravels along the system is a priority. It will be a function of resource delineation work ahead of the mining plan.

To date the gravels have been prospected through use of excavators and hand pitting, but this method denies the use of the same excavators for the mining of income generating gravels. Thus there is an opportunity cost with the current small fleet.

Its recovery is the latest success for TOMRA’s XRT sorting technology. Lucapa Managing Director Stephen Wetherall commented: “The recovery of the 227 ct diamond using the new XRT circuit justifies our investment in TOMRA’s large diamond recovery technology, which has more than paid for itself with the recovery of this one stone alone.

The AG milled product was screened into the following size fractions: -32+16 mm, - 16+8 mm and -8+4 mm, which were each spiked with specific numbers of vendor supplied natural diamonds, graphite tracers and Shore's diamonds, processed through the XRT sorter. Tests were completed at operational throughputs (presently up to 120 t/h) with all diamonds and tracers being recovered down to 4 mm, with very low concentrate yields.

Geoffrey Madderson, Segment Manager Diamonds at TOMRA Sorting Mining: “TOMRA’s XRT diamond recovery technology has yielded another diamond of exceptional size and quality.

As part of the new coarse rec ........