"To the end of 1930 Alaska, according to the records of the Geological Survey, had produced placer gold to the value of $258,962,000 from mines widely scattered throughout its length and breadth. The distribution of the placers from which the gold was recovered has been stated in more or less detail in the annual summaries published by the Geological Survey on the mineral industry of Alaska and also in its more complete reports on many of the individual mining districts. Although these summaries and reports have furnished information regarding the larger regions, they have not always given specific details regarding the smaller districts. Furthermore, there has been no recent attempt to assemble and publish in one place the scattered statistics regarding the placer-gold production by years and by regions and districts. The purpose of the present report is to set forth in condensed but comprehensive form a summary of the placer-gold production of Alaska so far as it can be determined from the available official records."

From abstract: The Kantishna mining district is about 90 miles west of McKinley Park station on the Alaska Railroad. The part of the district covered by this report comprises an area of about 72 square miles in the form of a strip 6 miles wide and 13 miles long. The bedrock is mainly a metamorphic series of rocks which within the area has been differentiated into a quartz-muscovite schist and a calcareous faces that ranges from limestone to chlorite schist. A few small dikes of quartz porphyry and diabase intrude the schist. The general structure trends N. 700 E., and from an axis that extends from Eldorado Creek northeastward to Spruce Peak the schistosity dips to the northwest and southeast. It is along this axis that the heaviest mineralization has occurred.

From abstract: This report presents the results of a reconnaissance of most of the mining districts of Oregon east of the Cascade Range, with the exception of the districts in the Sumpter quadrangle. The districts described are distributed through an area roughly coincident with the Blue Mountains, which extend over much of the northeast quarter of the State.

From Abstract: Two areas and their included mineral deposits, situated in Josephine County, southwestern Oregon, are described in this report. They lie within the Klamath Mountains, a region which is made up for the most part of rugged ridges trending in various directions but which, when viewed from higher summits, resembles a dissected plateau and is known as the Klamath peneplain. Rocks of both igneous and sedimentary origin are abundant in the districts described. The marine sedimentary rocks of the areas comprise a thick series of Carboniferous strata, with some interbedded volcanic rocks, and portions of the Galice formation, of Jurassic age, and of an Upper Cretaceous formation. The rocks of fluviatile origin include Tertiary conglomerate, Pleistocene valley fill, termed the " Llano de Oro formation," and somewhat later Pleistocene gravel and alluvium, in part glacial debris. Recent gravel is found along the present streams. The igneous rocks include several varieties of greenstone of probable Paleozoic and Mesozoic age and serpentine of late Jurassic or early Cretaceous age.

From abstract: The largest single metal-mining operation in the history of mining in Colorado has been developed at Climax, as a result of the increased use of molybdenum in the steel and other industries. Production of molybdenum at Climax was notable for a short period during the World War; it ceased from April 1919 to August 1924 but since then has shown a steady increase. In 1930 from 1,000 to 1,200 tons of ore was milled daily, using only one unit of the 2,000-ton mill. The mine has a reserve of broken ore sufficient to furnish 2,000 tons daily for 3 years and is being developed to continue to furnish this and a still further increased output as the use of the metal may warrant.

From abstract: The Girdwood district has been known for about 35 years to contain placer gold, but the source of the gold in veins was not discovered until about 1909. When the Alaska Railroad was completed through Girdwood it was hoped that the improved transportation facilities would enable the lode mines to operate at a profit and also to furnish tonnage to the railroad. Production from the quartz veins, however, has been negligible, although one placer mine has been operating steadily for several years.