Our diamond value chain comprises of processes that progressively add value to the diamond resource, from mining to sales. As the diamond resource passes through each intervention phase, additional value is added.
Drilling and blasting is used to break up millions of tonnes of ore and assist in the mining and recovery process
Kimberlite and waste rock are then loaded into massive trucks by large shovels and taken to the primary crusher and waste dumps respectively
Ore is broken down into manageable sizes through various stages of crushing and screening to reduce the size of the rock fed to the processing plant and release diamonds from the host rock
Diamonds are heavire (higher density) than the rock which hosts them. Once the ore has been reduced to the right sizes and diamonds liberated, heavy minerals, including diamonds are separated from light minerals in a process known as Dense Media Separation.
A Dense Medium know as ferrosilicon - powdered iron and silicon in water - is used to float light minerals and separate them from heavy minerals.
Waste material is sent from the DMS Plant to the Recrush Plant.
Here ore is again crushed using a more refined process. This plant helps liberate smaller diamonds not liberated by the initial treatment process. This process produces a concentrate.
Diamonds have several remarkable properties that we are able to exploit to recover them from the stream of prepared concentrate. They emit light unders X-rays enabling us to detect and separate them.
Diamonds repel water and are attracted to grease. When we mix the concentrate with water and pass it over a grease belt, the diamonds adhere tot eh grease.
Diamonds fluoresce under the laser sorters we use to further concentrate the processing stream.
Sorting and Sales
Diamond sorting, cleaning, packaging and weighing takes place in a Fully-Integrated Sorthouse (FISH) which is automated.
FISH maximises diamond security while optimising diamond sorting through the use of laser technology. Our diamonds are then sold to the DTC Botswana in Gaborone.
Here they are sorted into more than 12000 different categories before being sold by the DTCB to De Beers who, in turn, sell them to their clients at "sights" in Gaborone.
Thereafter, rough diamonds find their way to cutting and polishing centres where they are sold to manufacturers who produce diamond jewellery destined for the leading consumer markets.