Richard Alexander Fullerton Penrose, Jr., an eminent economic geologist, wrote important studies for state and national geological surveys, including the first on the Cripple Creek Mining District. He wrote more than 60 articles and books, most on ore deposits. He was a director of several mining companies, a college professor, and a mine owner, manager, and consultant. He traveled extensively to visit mines, and he was a confidant of his brother, Mining Hall of Fame inductee Spencer Penrose, and of Charles Tutt, Herbert Hoover, and Daniel Jackling, also Mining Hall of Fame Inductees.
R. A. F. Penrose wrote his Doctoral dissertation at Harvard on phosphates in Canada, and the U.S. Geological Survey later reprinted his work as a U.S.G.S. Bulletin. In 1887, the newly formed geological survey in Texas hired him for a geological survey in East Texas, and two years later, he was employed by the Arkansas Geological Survey.
In 1894, he accepted an offer to work with Dr. Whitman Cross for the U.S.G.S., preparing a detailed report on the newly formed Cripple Creek, Colorado, gold district. Their report, “Part II of The Geology and Mining Industries of the Cripple Creek District of Colorado,” was very popular with the mine owners of the district, who had great confidence in its contents. Penrose stated in the report that he felt that the gold mineralization in some veins would go to very great depths, contrary to opinions expressed by many others. His prediction was substantiated in later years as the mines increased in depth.
The following years were filled with mine examination in many places, and Penrose with a partner, Daniel Barringer, also bought and operated the Commonwealth mine in Pearce, Arizona. By 1896, Penrose was a Director of the Colorado-Philadelphia Reduction Co. in Colorado City, Colorado, along with his younger brother, Spencer. From 1899 to 1915, he was a member of the executive committee of the HANOVER Bessemer Iron Ore Association in Fierro, New Mexico and a Director of the Cripple Creek Sampling & Ore Company.
In 1903, Penrose resigned as President of Commonwealth Mining and Milling and traveled to Utah to become a founder of Utah Copper Company, along with Spencer Penrose, Daniel Jackling, and Charles MacNeil. Jackling wrote years later that “his counsel and support, financially and otherwise were of inestimable value in the Utah enterprise and the similar ones that followed it.” Those similar enterprises involved the development of major mines at Chino, New Mexico, and Ray, Arizona. Penrose became a Director of both properties. He also became a Director of Kennecott Copper Company, the Nevada Consolidated Copper Company, and the Braden Copper Company of Chile.
In addition to his business activity, R. A. F. Penrose supported many professional societies. His greatest interest was the Geological Society of America. He accepted its Presidency in 1930 just prior to his death in 1931. The bulk of his fortune was divided between the Geological Society of America and the American Philosophical Society.