Eight diamond mines are mentioned in the Ratnapariksa, but their locations are not recorded. As with other deposits seen during the past 400 years, flooding and erosion may well have caused them to disappear. The earliest reference in European literature appears to come from a Greek sailor in around 120 BC, who saw them next to river 'alluvions' and said there were "diggings of deep galleries".
If this is true, then they were being worked from underground, as well as from the surface at that time. Not until the 19th century was a detailed study made of where they were located or where they might have been. Needless to say that nowadays rough diamonds are mainly mined in KIMBERLIT mines in Afrika, Russia, Kanada and South Amerika.
All historical texts above from: Een Streling Voor Het Oog, Antwerpen 1997