Canada Silver Cobalt Works Inc. has announced that it has completed re-processing waste rock material from Castle Mine, in Gowganda, Ontario. Cobalt and nickel results are still pending.
Highlights of Waste Rock Re-Processing:
– Mine waste rock is potential pre-production plant feed.
– Mine waste rock can be mechanically sorted and upgraded by simple gravity concentration.
– Waste rock currently sitting outside the mine is potentially similarly mineralized as the stored waste rock left in the mine stopes.
The assays were performed on two separate size classes of the same mineralized material. Due to significant native silver in the waste rock, it is best to break down the sample to different size classes to find which size class the native silver and gold values are associated with. As this is a simple, single-pass gravity concentration, higher grades are likely after additional gravity concentration steps. Table 1 indicates that in the +20 mesh size fraction, the higher grades are due to the native metal component of the precious metals.
Waste rock from the Castle mine was mechanically sorted in preparation for crushing, grinding, screening and gravity concentration to produce a gravity concentrate for the recovery of silver and battery metals. The waste rock that has been put on the waste pile outside the mine by previous mine operators has the potential to be of similar grade as that left in the stopes underground.
The Company, as part of the proposed mine development for production mining, has already rehabilitated about 500 meters of the 1.2 kilometers of accessible First Level underground mine workings which can be accessed by an adit. Two hundred of the 500 rehabilitated meters have mined stopes above and have broken muck stored, potentially up to 10 meters deep in the stope, on the mine’s first level. Historically, mining companies drifted directly on the mineralized veins during mine production.
Based on the underground drilling done in 2019, the potential exists that, in addition to the 600 meters of stoped drifts that have already been mined, there exists up to a further 300 meters of stoped veins yet to access. With additional exploration, extensions of potential mineralized vein material can be identified to mine and process for the recovery of precious metals and battery metals.
In addition to the mine level plans, the company came upon plans for a ramp to be used to mine the mineralized material between the 11 existing mine levels. This would create a ramped mine operation allowing for hauling the ore up the main shaft. This will lead to an optimized mine design for future mine production.