Phillip L. Merritt
Phillip Leonidas Merritt (February 8, 1906 – November 14, 1981) was an American geologist who helped locate uranium for the Manhattan Project and later for the U.S. Atomic Energy Commission (AEC). He was born in Duluth, Minnesota, and came from a family with a mining background. He earned a geology degree from the University of Minnesota in 1928, then went to Columbia University, where he earned his master’s degree in 1930 and a PhD in 1934. His PhD thesis, the Seine-Coutchiching Problem, was supervised by Charles Peter Berkey.
After college, Merritt worked in Africa searching for copper for the Rhodesian Selection Trust. He returned to the United States in 1929 and, during the Great Depression, took a job with the Columbian Department of Mines, then worked as a geologist and mineralogist for American Cyanamid in New York City starting in 1936, doing mineral and oil explorations and publishing papers.
In 1942, Merritt joined the U.S. Army Corps of Engineers and the Manhattan Project, becoming a captain and later heading the Raw Materials Section of the Manhattan District’s Madison Square Area (1943–1946). Although the main project moved to Oak Ridge, the materials section stayed in New York. Merritt traveled widely to locate uranium sources, visiting sites such as the Eldorado Mine in Canada, the Shinkolobwe mine in the Belgian Congo, and vanadium mines on the Colorado Plateau. He played a key role in identifying that tailings from Shinkolobwe contained up to 20% uranium ore, a major finding for U.S. uranium sourcing. For his service, he received the Legion of Merit in 1946. He married Beatrice Wolff on November 2, 1946, and left the Army at the end of the year with the rank of major.
When the Manhattan Project ended, the United States Atomic Energy Commission took over in 1947, and Merritt continued as a civilian, directing the raw materials program. He helped expand uranium search efforts to Blind River in Canada and to South Africa, and he worked with MIT to develop methods for recovering uranium from South African gold ores. In the 1950s, he directed searches by the U.S. Geological Survey and the U.S. Bureau of Mines to find domestic uranium sources, which led to discoveries in Utah, New Mexico, and Wyoming.
The AEC’s exploration office moved to Washington, D.C., in 1954, but Merritt stayed in New York. He left the AEC to become a consultant for the E.J. Longyear Company in 1954, assessing ore reserves and their economic value. He received the University of Minnesota’s Outstanding Achievement Award in 1956.
In 1961, Merritt moved to Salt Lake City and became vice president of exploration for the Hidden Splendor Mining Company (which later became Atlas Minerals). Atlas attempted to diversify beyond uranium and eventually failed; the company moved to Denver in 1966, but Merritt stayed in Salt Lake City. He later worked as a consultant for electric utilities that needed uranium for their nuclear reactors. Merritt died in Salt Lake City in 1981 after a battle with cancer. His papers are housed at the American Heritage Center, University of Wyoming.
This page was last edited on 2 February 2026, at 06:05 (CET).