"The Upper Puruni, downstream from Majuba Hill/Wynamu confluence has a long history of alluvial gold workings from the 1930's to the present, and mining with 9 dredges was underway in that area during the period of the field programme. This project was designed to investigate the extent of gold mineralisation in the area, and to determine whether any other types of mineralisation occurs."

http://www.ggmc.gov.gy/uppur.html