Comminution and Liberation
Before a diamond is even processed, it must be mined first. The mineral is recovered from ore through a process known as comminution and liberation. Comminution is the breakage of larger ore into smaller particles. The liberation is the process of removing the incorporated diamond from the ore. In some instances, after larger diamonds have been processed, the ore may go through another re-crush phase to try to remove smaller diamonds.
Dense Medium Separation
The ore is placed into a ferrosilicon mix. The ore will then be scrubbed, cleaned, and processed. Material that is no longer deemed profitable will be rejected and dumped. The heavier minerals that sink in the ferrosilicon mix usually provide the richest diamond concentrate.
Recovering the Diamonds
Once the concentrate is processed, it is then time to recover the diamonds. In most instances, the diamond concentrate will go through an X-ray sorter. Since diamonds fluoresce when exposed to radiation, sensors go off when flashes of light are thrown off by them. Once the light is detected, the diamonds are expelled from the process stream.
Once a diamond has been processed and deemed as profitable, it will be acid-cleaned. It will then go through a process of cleaning, weighing and finally preparation before being sold.