Report issued by the U.S. Bureau of Mines over state mine inspection reports from 19 U.S. states. The information in the reports includes details of accidents, locations that specific accidents occurred, and proposed remedies for prevention of future accidents. This report includes tables.

From Introduction: "A review is given of the nomenclature, sources, imports, statistics, common methods of preparation, and testing of mineral pigments. A description of the Deer Park-Spokane colored-clay district and the laboratory methods of preparation of these colored clays, ochers, and siennas follows. The following report is merely preliminary in nature, only three months during the summer of 1927 being devoted to the laboratory investigation."

Report issued by the Bureau of Mines over the production methods and uses of plastic magnesia. Methods, properties, and uses of plastic magnesia are discussed. This report includes tables, illustrations, and photographs.

From Introduction: "On account of extensive folding and faulting of the coal measures, mining in Washington presents many difficulties; therefore a description of the methods employed at some of the mines may be useful in planning operations in other regions, and is presented in this bulletin."