The Strength of the Operational Activities
Sotkamo Silver's strength lies in its expertise in mining and operational activities. Together with an organisation competent in enrichment operations, the company has been able to increase the capacity of the enrichment plant and improve its utilisation rate to an excellent level, which also improves the Company's cost efficiency. Once the success of the organisation and the mill have been consoli-dated, the operations of the entire mining operations can be reproduced in a sustainable and responsible manner in new projects.
Mining is done dominantly from the underground mine but a small open pit has been planned to access the ore body near the surface. Underground mining is conducted by longitudinal bench and fill method. The stopes will be back-filled with a rock fill. The open pit mining has been started from the outcropping mineralization. According to the mine plan, the final depth of the open pit will be ca. 45 meters.
Mining is conducted by the mining contractor, Veljekset Toivanen Oy, under the supervision of the Sotkamo Silver geology and mining personnel.
Decline (green), ventilation shaft (blue) and current designs for open pit (brown), stopes (grey) and access tunnels etc. (red).
The mined ore is crushed and milled before the flotation process to desired grain size. Crushing is done in two phases followed by milling in the bar and ball mills. The flotation process is conducted in the stages. The first stage is the silver-gold-lead flotation which is followed by the zinc-silver flotation and pyrite flotation stages. Each flotation stage consists of several steps. Residue of the flotation is pumped as a slurry to the tailings management facility (TMF) where material is deposited and water circulated back to the flotation process.
The final products of the processing are:
1. Silver-gold-lead (Ag-Au-Pb) concentrate
2. Zinc-silver (Zn-Ag) concentrate
3. Pyrite-silver (FeS2-Ag)- concentrate.
Silver-gold-lead concentrate is transported in the containers to smelter for further processing and zinc-silver concentrate is trucked to customer's facilty. Currently, pyrite-silver concentrate is stored for possible utilisation.