Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-27T08:07:55.607Z Has data issue: false hasContentIssue false

Redskin Granite: a rare-metal-rich Precambrian pluton, Colorado, USA

Published online by Cambridge University Press:  05 July 2018

G. A. Desborough
Affiliation:
US Geological Survey, Denver, Colorado, USA
S. D. Ludington
Affiliation:
US Geological Survey, Denver, Colorado, USA
W. N. Sharp
Affiliation:
US Geological Survey, Denver, Colorado, USA

Summary

The Precambrian Redskin stock is a high-silica alkalic granite that forms a late pluton related to the 1000 Ma-old Pikes Peak batholith. Zircon, fluorite, fluocerite, ilmenorutile, columbite, biotite, magnetite, and hematite are the most abundant accessory minerals. Thorite, monazite, and xenotime are sparse, and cassiterite and topaz very rare. The principal residences of Sn, Nb, and Ta are ilmenorutile and columbite. The occurrence of cassiterite intergrown with biotite and columbite and the high contents of Nb and Ta in cassiterite are evidence that cassiterite is also a primary mineral. The high concentrations of certain trace elements indicate a high degree of fractionation of magma prior to emplacement of the Redskin Granite. An extremely low crystallization temperature for the granite is indicated by the compositions of albite and K-feldspars, the presence of Fe-rich dioctahedral mica, the absence of Ti in magnetite, and the low content of Ti in biotite. This low crystallization temperature seems due largely to the high concentrations of F, Rb, and other volatile elements in the magma.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1980

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bailey, (J. C.), 1977. Chem. Geol. 19, 142.CrossRefGoogle Scholar
Barker, (F.), Wones, (D. R.), Sharp, (W. N.), and Des-borough, (G. A.), 1975. Precambrian Res. 2, 97–160.CrossRefGoogle Scholar
Barker, (F.) Hedge, (C. E.), Millard, (H. T., Jr.), and O'Neill, (J. R.), 1976. Colo. School Mines, Prof. Contr. 8, 4456.Google Scholar
Buddington, (A. F.) and Lindsley, (D. H.), 1964. J. Petrol. 5, 310–57.CrossRefGoogle Scholar
Czamanske, (G. K.) and Wones, (D. R.), 1973. Ibid. 14, 349–80.Google Scholar
Desborough, (G. A.) and Mihalik, (P.), 1980. U.S. Geol. Survey Open-file Rep. 80661, 16.Google Scholar
Desborough, (G. A.)and Sharp, (W. N.), 1978. Econ. Geol. 73, 1749–51.CrossRefGoogle Scholar
Desborough, (G. A.) Sharp, (W. N.) Kamilli, (R.), Gunow, (A.), and Taylor, (R. B.), 1978. 9th Reg. Conf.for Study of Min. in Pol. Sec. on Micro-scale, Cent. of Soc. Franc. de Min. et Cristall.Google Scholar
Glyuk, (D. S.), Bazarova, (S. B.), and Trufanova, (L. G.), 1977. Ezhegodnik Sibirsk Inst. Geochim. (yearbook Siberian Inst. Geochem. for 1976), 170–5.Google Scholar
Gunow, (A. J.), 1978. Univ. of Colo. (MS thesis), 287.Google Scholar
Gunow, (A. J.) Ludington, (S. D.), and Munoz, (J. L.), 198. Econ. Geol. (in press).Google Scholar
Hawley, (C. G.), 1969. U.S. Geol. Surv. Prof. Paper 608-A, 44.Google Scholar
Hawley, (C. G.) and Wobus, (R. B.), 1977. Ibid. 608-B, 77.Google Scholar
Hawley, (C. G.) Huffman, (C., Jr.), Hamilton, (J. C.), and Rader, (L. R., Jr.), 1966. Ibid. 550-C, I3847.Google Scholar
Hildreth, (E. W.), 1979. Geol. Soc. Amer. Sp. Paper 180, 4375.Google Scholar
Ludington, (S. D.), 1974. Univ. of Colo. (Ph.D. thesis), 167.Google Scholar
Ludington, (S. D.) and Munoz, (J. U), 1975. Geol. Soc. Am. Abstr. 7, 1178.Google Scholar
Ludington, (S. D.) Sharp, (W. N.), McKowan, (D.), and Barker, (F.), 1979. Ibid. 11, 469.Google Scholar
Munoz, (J. L.) and Ludington, (S. D.), 1977. Am. Mineral. 62, 304–8.Google Scholar
Shaw, (H. R.), Smith, (R. L.), and Hildreth, (E. W.), 1976. Geol. Soc. Am. Abstr. 8, 1102.Google Scholar
Streckeisen, (A.), 1976. Earth Set Rev. 12, 133.CrossRefGoogle Scholar
Tischendorf, (G.), 1974. Int. Geol. Cong. Prog., MAW AM, 2, 4196.Google Scholar
Turekian, (K. K.) and Wedepohl, (K. H.), 1961. Geol. Soc. Am. Bull. 72, 175–92.CrossRefGoogle Scholar
Tuttle, (O. F.) and Bowen, (N. L.), 1958. Geol. Soc. Am. Mere. 74, 153.Google Scholar
Velde, (B.), 1965. Am. J. Sci. 263, 886–913.CrossRefGoogle Scholar
Velde, (B.) 1972. Contrib. Mineral. Petrol. 37, 235–47.CrossRefGoogle Scholar
Whitney, (J. A.), and Stormer, (J. C.), I977. Am. Mineral. 62, 687–91.Google Scholar
Wobus, (R. A.) and Anderson, (R. S.), 1978. U.S. Geol. Survey J. Res. 6, 8194.Google Scholar
Wones, (D. R.) and Eugster, (H. P.), 1965. Am. Mineral. 50, 1228–72.Google Scholar