The HPGR technology has been in existence for many years. It was originally developed and applied in the cement industry and was introduced into the mining industry in the early 1980s for the crushing of kimberlite ore in diamond mines. The application and advantages of using these grinding rolls to extract diamonds is now well established. HPGR technology was also successfully introduced and applied in the iron ore and limestone industries and is now making in-roads into hard rock mining applications.