Burchett, R. R., 1968. Directory of Nebraska Quarries, Pits, and Mines (RR-1): 32 pp., size 8.5" x 11". Description: This report is a directory of the known (as of 1968) producers of stone, sand and gravel, clay and shale, and volcanic ash in Nebraska. It has been prepared to assist those interested in producing or utilizing the rock and mineral resources of Nebraska. Individual tables were prepared for limestone, sand and gravel, clay and shale and volcanic ash. A map showing locations of active mines, pits and quarries in the state during 1967 is included. Note: publication RR-5 (1971) updates this 1968 version. Out of print, unbound copy available.