An improvement in a rock picking machine having a frame with ground wheels supporting the frame, a table with a grate over which rocks are moved and discharged into a bucket rearwardly pivotally mounted on the frame, and a conveyer forwardly pivotally mounted on the table for moving rocks up the grate....http://www.google.com/patents/US5141058?utm_source=gb-gplus-sharePatent US5141058 - Rock picking machine
