by E.O. Gooch, R.S. Wood and W.T. Parrott, 6 x 9-inch soft-cover book, 65 pages, 10 plates include folded 16 x 31-inch black and white 1:1,000,00-scale map, 1960. Materials used for highway aggregate in Virginia range from highly metamorphosed rocks of Precambrian age to unconsolidated sand and gravel deposits of Recent age. Limestone, dolomite, and quartzite are produced in the Valley and Ridge province. Granite, various types of gneiss, diabase, basalt, marble, limestone, sandstone and conglomerate are produced in the Blue Ridge and Piedmont provinces. Sand and gravel are produced in the Coastal Plain province. Aggregate is classified into grades A, B, and C on the basis of three physical properties: abrasion loss, specific gravity, and absorption. Tests used in determining the physical properties are described in the text and the specifications for each grade are listed. Aggregate producers are listed by province with descriptions of the geology of each pit and quarry, physical test data on the aggregate, and size of the operation or rate of production during 1957 or 1958. Sixty-eight locations plotted on accompanying maps.
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