Searchlight Minerals Corp. announced that it has run its pilot autoclave on slag material taken from the Clarkdale Slag Project and furthermore, the results of the latest test confirmed gold in hand from fire assay. Test results: The ninth and latest pilot autoclave test demonstrated that 0.42 ounces per ton gold was leached into solution from the slag sample containing 0.48 opt gold, which represents an estimated gold recovery of 87.5%.

While past test work had relied upon 'wet chemistry' electronic determination, these latest results were determined by analyzing gold metal extracted by standard fire assay techniques. Solution values were determined by evaporating the pregnant leach solution and fire assaying the residual solids to produce a gold bead in hand. Likewise, the finely ground slag going into the large pilot autoclave and the leached residue after the test were also fire assayed and the resultant gold beads were used to calculate gold grades and leach efficiency.

This is the second autoclave test that has verified the gold grade of the slag by fire assay. Electrowinning tests are currently underway to recover gold as metal from the PLS.