Rockhaven Resources Ltd. announced encouraging results from comprehensive pre-concentration (sorting) test work on bulk samples of material selected from within the mineral resources at its 100% owned Klaza Au-Ag-Pb-Zn deposit, Yukon1. The test work results demonstrate the potential effectiveness of pre-concentration of Klaza mineralisation at a coarse crush size, by doubling the grade of material entering the mill and reducing the mill feed tonnage by over 50%, with only minor losses in metal. Positive impacts on potential future operations that may result from the use of pre-concentration include a material reduction in the amount of flotation tails, a significantly smaller grinding and flotation circuit and, potentially, lower overall capital and operating costs for such an operation.

Beyond cost-efficiencies related to milling fewer tonnes for similar contained metals, other advantages of using this technology may include a significant reduction in the amount of Flotation tails, less haulage of material from underground operations, and lower mining cut-off grades by upgrading material that was previously expected to fall below future economic cut-off grades. Trade-off studies will begin shortly to optimize the degree to which pre-concentration could be adopted, which will help to set the stage for the upcoming mineral resource estimate and pre-feasibility study. Once the results are compiled and interpreted, the optimal density settings are determined.

Phase I began with scanning 300 mineralized and unmineralized rock pieces using TOMRA XRT detection technology from split drill core samples collected at Klaza. Detection information from the XRT indicated that there was good contrast between particles which could lead to a high recovery and low yield on a bulk scale. These were split into two "life-of-mine" feed grade composites (from Klaza and BRX) and one "Low Grade" composite.

The Low-Grade composite included a mix of lower grade material from the BRX and Klaza Zones and assayed below the cut-off grades used in the current Klaza Deposit mineral resource estimate. The grades of all three composites are shown below: Each of the three composites was crushed to less than 63mm in size.