Diamonds possess unique properties that can be exploited when developing a flow sheet for diamond recovery. For example, diamond luminescence describes the glow a diamond can produce when its atoms are excited by a high-voltage energy source, such as x-rays. The luminescence is detected by a photomultiplier tube that can activate an ejection mechanism to remove the luminescent diamond from the stream of other non-luminescent minerals. The luminescence intensity in the diamond does have some correlation to the diamond type.
Variable concentrations and arrangements (aggregation states) of nitrogen atoms within the carbon crystal lattice (Type I diamonds) can influence the intensity, and thereby recoverability, of a diamond using x-ray luminescence (XRL). Type II diamonds contain no detectable nitrogen and often exhibit weak to no luminescence making them more difficult to recover reliably with XRL. Scavenging technologies such as laser-raman and grease table are then introduced as an additional process to ensure the recovery of low-luminescent stones. This can make recovery flow sheets more complex and difficult to maintain. Knowing more about the population of the diamond parcels prior to designing a recovery circuit can aid in sourcing the appropriate equipment.
In this webinar, Lucy Hunt and Mike McCubbing from SRC’s Applied Diamond Services team will explain the various diamond types and how they are identified, as well as the properties they exhibit as it relates to processing and recovery. They will also discuss how new technologies, such as X-ray transmission (XRT), can improve the efficiency of diamond recovery.
