Radium, uranium, and vanadium deposits of southwestern Colorado. R.C. Coffin. 231 pages. 4 plates (1:126,720 and 1:63,630). 53 figures. Digital PDF download. B-16D
Note that Bulletin 16, which was published in 1921, was preceded in 1920 by a “Preliminary Statement from Bulletin 16 on The Carnotite Area of Southwestern Colorado (Uranium, Radium, and Vanadium)”, also by R.C. Coffin. The reason for the preliminary paper was “The unusual activity in the mining of carnotite and its related ores has created a demand for information concerning them. In order that the results of this survey be made public as soon as possible these preliminary statements are published in advance of the more complete bulletin.” The Preliminary Statement from Bulletin 16 was 28 pages and included four plates.
Excerpted from the 1921 Bulletin introduction:
The area covered by this report includes the exploited carnotite districts of southwestern Colorado, together with certain extended portions of these districts, some of which are believed to be well worth prospecting. The objects of the survey were: To prepare a general base map of the region; to determine and map the boundaries of the McElmo formation in which all the commercial deposits of carnotite have thus far been found, and to prepare a report on the district to serve as a guide in prospecting and an aid in the development of the mineral resources of the region.
This 1921 report is organized as follows: Introduction, Chapter I. Geography, Chapter II. General geology, Chapter III. Structural geology, Chapter IV. Economic geology of carnotite and its related ores, Chapter V. Geology of special areas, and Chapter VI. Miscellaneous economic materials.