U.S. Geological Survey Certificate of Analysis
Mica Schist, SDC-1
Material used in the preparation of this standard was collected in 1963 from the Washington D.C. area. The material is probably of late Precambrian age, and examination of hand specimens reveals a dark gray pervasively foliated muscovite-quartz schist with a homogeneous thinly streaked texture (Flanagan, 1976).
Element concentrations were determined by cooperating laboratories using a variety of analytical methods. Certificate values are based primarily on international data compilations (Abbey, 1983, Gladney and Roelandts, 1988, Govindaraju, 1994). Initial USGS studies (Flanagan, 1976) provide limited background information on this reference material.
|Oxide||Wt %||±||Oxide||Wt %||±|
revised March 1995
David B. Smith
Central Region Mineral Resources Team (formerly Branch of Geochemistry)
Abbey, S., 1983, Studies in "Standard Samples" of Silicate Rocks and Minerals 1969-1982: Canadian Geological Survey Paper 83-15, p. 114.
Flanagan, F.J., 1976, Descriptions and Analyses of Eight New USGS Rock Standards: U.S. Geological Survey Professional Paper 840, 192 p.
Gladney E.S., and Roelandts, I., 1988, 1987 Compilation of Elemental Concentration Data for USGS BHVO-1, MAG-1, QLO-1, RGM-1, SCo-1, SDC-1, SGR-1, and STM-1: Geostandards Newsletter, 12:253-362.
Govindaraju, K., 1994, 1994 Compilation of Working Values and Descriptions for 383 Geostandards: Geostandards Newsletter, 18:1-158.
|Fe2O3T||Total iron expressed as Fe2O3|
|Ctot||Total carbon concentration|
|Stot||Total sulfur concentration|
|Wt %||Percent of total element concentration|
|µg/g||Total element concentration expressed as micrograms of element per gram of solid sample|
|±||One standard deviation|
Unless otherwise indicated total element concentrations are reported for material on an as-received basis, i.e., no drying.
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