Margaret B. Fuller Boos' primary interest was in mapping and interpreting the
granite intrusives on the
Colorado Front Range and discovered the first
lithium pegmatite in the front range. During her time as a geology professor, she mapped the granite intrusives and pegmatites in the
Denver Mountain Parks area. In 1922, Boos mapped the
Precambrian area north and south of the
Big Thompson River, as well as the extent of the
Longs Peak and
Mt. Olympus granites. In 1924, she continued her research in the Big Thompson River, yet this time focusing on the
glacial features along the river. After her marriage to Charles Maynard Boos, the newly weds both went out to work for
Empire Gas and Fuel as petroleum geologists. In the summer of 1928, she was offered a job as a part-time ranger-naturalist at
Rocky Mountain National Park. After accepting the job, offered to her by the superintendent
Roger Toll, she became the first female ranger-naturalist at Rocky Mountain National Park. Toll wrote to her that he "[would] prefer a man for the job", but her expertise outshined her status as a woman. One year later, in 1929, Roger Toll offered Boos a full-time position working at the Park, but she graciously declined the offer and returned to the petroleum industry. During the summers of 1929 - 1931 Margaret and Charles spent their time elaborating and expanding on Margaret's "Hard Rock" thesis. The two combined their work with the
Colorado School of Mines and the
University of Wisconsin; this led to a series of presentations and conversations, resulting in their summary paper on Longs Peak-St.Vrain Batholith. The Boos' work was considered important to geology at the time because the
plutons and their contacts had not been previously determined. Margaret began teaching once again at the
University of Denver in
South Denver, Colorado, where she and her student, Esther Aberdeen, published a paper with a map describing these plutons. Boos began to further investigate the pegmatites throughout the
Denver Mountain Parks region. Margaret then notes that there are
tourmaline-bearing and
beryl-bearing pegmatites. This began further research into beryl,
mica,
tantalum and
lithium pegmatites. In 1943, Margaret began working full-time for the
Bureau of Mines on their strategic minerals program. She transferred to the
United States Bureau of Reclamation (1945) in order to move back to Denver. In 1947, Boos quit the bureau to become a geological consultant with her office at home. She then published her pegmatite conclusions in 1945, which contained a map of the Denver Parks area covering 540 square miles of the area. Afterwards, Margaret continued as an active geologist until 1968. Margaret and her husband also worked for Sharples Oil and Carter Oil for some time. Their experiences in these companies, and focus on stratigraphy, led to one of their most significant contributions; a paper about the tectonics of the eastern flank and foothills of the Front Range in Colorado. == Pegmatite in the Colorado Front Range ==