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Album caption and index card: Ore from Queen mine, Ward district, showing wolframite (light gray) and quartz (dark gray) cutting coarse pyrite (white). Boulder County, Colorado. Notes: Published as figure LXVIII-D in U.S.Geological Survey Professional paper 223. 1950.
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Album caption and index card: Coarse vuggy quartz (white) cut by intergrown hematite and fine-grained quartz (black). from Rogers breccia reef west of Peewink Mountain. Boulder County, Colorado. Notes: Published as figure XXIII-A in U.S.Geological Survey. Professional Paper 223. 1950.
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Album caption and index card: Photomicrograph of ore from nickel mine, a mile west of Gold Hill, showing part of area included in photograph 712. Pyrite (py) and pyrrhotite (pr) replaced by chalcopyrite (c). Niccolite (n) replaces pyrrhotite, which replaces amphibole (a). Boulder County, Colorado. Notes: Published as figure XVII-E in U.S.Geological Survey. Professional Paper 223. 1950.
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Album caption: View looking W. and N.W. toward Boulder from a point approximately 4 miles S. of Lafayette on the main Denver...Boulder concrete highway. Shows prominent benching at the sides of the valley of Boulder Creek where it leaves the mountains. The benching is due to the development of Flagstaff Hill, Mt. Morrison and lower surfaces. (See T.S. Lovering photo number 644, lts000644).
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Album caption and index card: Differential erosion of the Hoosier breccia reef near the head of Black Tiger Gulch, 6 miles west of Boulder. The country rock of this silicified northwest fault zone is Boulder Creek granite. Wall-like outcrops of this kind have give rise to the local use of the term "dikes" in naming these faults. Boulder County, Colorado. Notes: Published as figure XIX in U.S.Geological Survey. Professional Paper 223. 1950.
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Album caption and index card: The Front Range. The Snowy Range west from North Boulder. Among the hills in the distance are the town and the famous mines of Caribou. The town of Middle Boulder and the reduction-works are about 4 miles below, in the valley. Beyond the hills the very tip only of Arapahoe can be seen. Boulder County, Colorado. 1873.
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Album caption and index card: Gneissic hornblende diorite half a mile north of Nederland, near the center of a mass about 100 feet wide. The coarse grained and slightly foliated structure of this outcrop is characteristic of the formation. Boulder County, Colorado. Notes: Published as figure IX-B in U.S.Geological Survey. Professional Paper 223. 1950.
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The Hoosier shaft house of the Wolf Tongue Mining Company, two miles northwest of Nederland. Boulder County, Colorado. September 3, 1909.
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Album caption and index card: Typical coarse-grained quartz-pyrite-sphalerite ore of the Ward district from 200-foot level of Queen mine. Bands of pyrite (p) and quartz (q) are earlier that the sphalerite (s). Area included in photo no. 729 shown by small rectangle. Boulder County, Colorado. (Specimen) Notes: Published as figure LXVIII-B in U.S.Geological Survey. Professional Paper 223. 1950.
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Silty shale and basal sandstone of the Plainview sandstone member of the South Platte formation in disconformable contact (at man's hand) with argillaceous sandstone of the underlying Lytle formation on hogback south of Eldorado Springs. Boulder County, Colorado, ca. 1951. Published as figure 9 in U. S, Geological Survey Professional Paper 274-B. 1955.
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Album caption: View looking W. and N.W. toward Boulder from a point approximately 4 miles S. of Lafayette on the main Denver...Boulder concrete highway. Shows prominent benching at the sides of the valley of Boulder Creek where it leaves the mountains. The benching is due to the development of Flagstaff Hill, Mt. Morrison and lower surfaces. (See T.S. Lovering photo number 645, lts000645).
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Characteristic appearance of productive part of an average size tungsten vein, looking directly up at Cold Spring vein in roof of stope on 1930 ore shoot 100 feet level 4, west of Old shaft. sg, Sericitized granite; qg, silicified and sericitized fragments of granite; f, intergrown ferberite and horn quartz. Boulder County, Colorado. Pre-1950. Figure 23-C, in U.S.Geological Survey Professional paper 223. 1950. Figure 52, in U.S.Geological Survey Professional paper 245. 1953.
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Album caption and index card: Granite gneiss (gneissic aplite) in the Idaho Springs formation, seven-tenths of mile north of Nederland, the seam of gneissic aplite which represents the granite gneiss formation underlies the scale and is bordered by a thin seam of pegmatite. The dark colored strongly foliated schist with which the gneiss is interlayered is its common constituent. Boulder County, Colorado. Notes: Published as figure IX-A in U.S.Geological Survey. Professional Paper 223. 1950.
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Mill on "Copeland property" of the Primos Exploration Company, South Boulder Creek, 1 1/2 miles north of Crescent station on the Moffat Road and 10 miles southwest of Boulder, looking northeast. Boulder County, Colorado. March 6, 1917.
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Small slump in Laramie Formation on Boulder County road 2 miles west of Jefferson County Airport. Boulder County, Colorado. 1973.
map background search result map search result map Roadway under Castle Rock. Boulder County, Colorado. 1873. The Snowy Range west from North Boulder. Boulder County, Colorado. 1873. James Peak from near North Boulder, a distance of about 20 miles. Grand and Boulder Counties, Colorado. 1873. View in Boulder Canyon, near Castle Rock. Boulder County, Colorado. 1873. Granite gneiss in the Idaho Springs formation, north of Nederland. Boulder County, Colorado. circa 1932. Gneissic hornblende diorite, north of Nederland. Boulder County, Colorado. circa 1932. Photomicrograph of ore from nickel mine, west of Gold Hill. Boulder County, Colorado. circa 1932. Differential erosion of the Hoosier breccia reef near the head of Black Tiger Gulch, west of Boulder. Boulder County, Colorado. circa 1932. Coarse vuggy quartz cut by intergrown hematite and fine-grained quartz. Boulder County, Colorado. circa 1932. Coarse-grained quartz-pyrite-sphalerite ore, Queen mine. Boulder County, Colorado. 1932. Ore from Queen mine. Boulder County, Colorado. 1932. Silty shale and basal sandstone of the Plainview sandstone member of the South Platte formation. Boulder County, Colorado. Circa 1951. View looking west and northwest toward Boulder, Boulder County, Colorado. Circa 1940s. View looking west and northwest toward Boulder, Boulder County, Colorado. Circa 1940s. Roadway under Castle Rock. Boulder County, Colorado. 1873. The Snowy Range west from North Boulder. Boulder County, Colorado. 1873. View in Boulder Canyon, near Castle Rock. Boulder County, Colorado. 1873. Silty shale and basal sandstone of the Plainview sandstone member of the South Platte formation. Boulder County, Colorado. Circa 1951. View looking west and northwest toward Boulder, Boulder County, Colorado. Circa 1940s. View looking west and northwest toward Boulder, Boulder County, Colorado. Circa 1940s. James Peak from near North Boulder, a distance of about 20 miles. Grand and Boulder Counties, Colorado. 1873. Granite gneiss in the Idaho Springs formation, north of Nederland. Boulder County, Colorado. circa 1932. Gneissic hornblende diorite, north of Nederland. Boulder County, Colorado. circa 1932. Photomicrograph of ore from nickel mine, west of Gold Hill. Boulder County, Colorado. circa 1932. Differential erosion of the Hoosier breccia reef near the head of Black Tiger Gulch, west of Boulder. Boulder County, Colorado. circa 1932. Coarse vuggy quartz cut by intergrown hematite and fine-grained quartz. Boulder County, Colorado. circa 1932. Coarse-grained quartz-pyrite-sphalerite ore, Queen mine. Boulder County, Colorado. 1932. Ore from Queen mine. Boulder County, Colorado. 1932.