Quantitative Assessment of PGE Resources in Finland

The PGE endowment of Finnish bedrock has been assessed to one km depth using the three part quantitative mineral resource assessment method developed by U.S. Geological Survey. Contact-type and reef-type PGE deposits were included in the assessment. These deposit types are related to similar to 2.44 Ga layered mafic-ultramafic intrusions in northern Finland and contain the majority of Finnish PGE resources. There are eight known contact-type deposits in Finland with a combined endowment of 0.225 Mt Ni, 0.43 Mt Cu and 284 t PGE+Au. No well-explored reef-type deposits with comprehensive grade-tonnage data are known. Deposit models were constructed for both deposit types using publicly available data. Tracts permissive for the deposit types were defined and the number of undiscovered deposits within each tract was estimated. The expected (mean) numbers of undiscovered deposits for the contact and reef types are 30 and 22, respectively. The estimates were combined with grade-tonnage models using Monte Carlo simulation to calculate the amounts of undiscovered Pt, Pd, Au, Ni and Cu metal. The combined known and estimated resources in contact-type PGE deposits in Finland are 502 t Pt, 1906 t Pd, 206 t Au, 2.5 Mt Ni, and 3.4 Mt Cu.