Distribution of gold in tin-rich samples from the Corvo Orebody, Portugal

The mineralogical distribution of gold in samples from the Corvo orebody, i n the Iberian Pyrite Belt of Portugal, was determined in a detailed study o f a few hand samples of RT ("rubane tin") ore. In one sample, 42% of the go ld occurs invisibly in pyrite I, pyrite TT, and arsenopyrite, with the bala nce assumed to be carried by cassiterite, which makes up 56.5 wt.% of the s ample. Extrapolation of these results to a sample of high-grade tin concent rate (68.99 wt.% Sn) suggests that cassiterite in the concentrate contains about 149 ppb Au, representing 88% of the total gold in the concentrate. Th ese results have implications on the metallogeny of the Neves-Corvo volcano genic massive sulfide deposit as well as on the metallurgical treatment of the ores.