A new type of rocks with elevated gold contents - high-alumina metasomatite
s - has been distinguished in the Archean Olondo greenstone belt. The miner
alogical and petrochemical features of zonal metasomatites are considered.
It is suggested that these rocks resulted from periodical inflows of mantle
-derived fluids to the zone of intense transformation of metamorphosed gabb
ro-amphibolites to schists.