OREAS 37 is a medium grade zinc ore matrix-matched certified reference material (MMCRM) prepared by Ore Research and Exploration. It is one of 3 MMCRM's sourced from the Gamsberg Zn deposit located in the Northern Cape Province of South Africa, approximately 20km west of the Black Mountain mine. Gamsberg is a stratiform base metal Broken Hill Style (BHS) deposit located in the mid-proterozoic Bushmanland Province of the Namaqualand Metamorphic Complex (NMC) of South Africa. The NMC is a highly deformed and metamorphosed supracrustal succession of dominantly pelitic schists and quartzites, deposited on a regionally extensive 2000 Ma basement (Rozendal & Stalder, 2001). The stratiform ores have a close spatial and genetic association with metamorphosed chemical sediments including manganiferous iron formations, quartz-garnet rocks (coticules), Ca-Mn marbles and barite (Rozendal & Stalder, 2001).
CRM Code |
Principle Certified Values |
State |
Matrix |
Mineralization |
OREAS 37 |
Zn 6.26% |
Ag 5.0ppm |
Pb 0.615% |
primary |
meta-sediment/sulphide |
Broken Hill Type |