Certification of four North‐American Gypsum Rock Samples Type: Calcium Sulphate Dihydrate, CaSO₄.2H₂O, GYP‐A, GYP‐B, GYP‐C and GYP‐D

Abstract

Four natural gypsum rock samples were prepared and certified for major elements and some trace elements by the Analytical Group of Domtar Inc., Research Centre in Senneville (Montréal), Québec, Canada with the cooperation of Domtar Gypsum Products Laboratory in Caledonia, Ontario, Canada. The analytical round‐robin results received from 29 participating laboratories were statistically evaluated, summarized, and form the basis of this paper. These certified reference materials are primarily intended as calibration standards for the determination of major and minor elements in gypsums and gypsum related minerals and products. As certified gypsum rock samples were not available on the North‐American or world markets, these may be particularly important not only to the gypsum and cement industries, but also to geochemists, geologists and analysts of minerals and ores.

Geochemistry of the Upper Permian Ca-2 Deposits of the Løgumkloster-1 Well, South Denmark

“…In Table 2 are given the recommended values of the standard rocks (Govindaraju, 1984;Abbey, 1983;Kocman & Woodger, 1986). A reasonable agreement exists between these values and our determinations (Dansk Boreselskab, 1981 ).…”

“…The results of the INAA analysis are listed in Table 1. The standard rocks included are MAG-1 marine mud from U.S. Geologic Survey (Govindaraju, 1984;Abbey, 1983), GXR-1 and GXR-2 soils (Abbey, 1983), and GYP-A, GYP-B, GYP-C, and GYP-D gypsum samples (Kocman & Woodger, 1986 both from the surface of the core and from inside fractures formed by the relief of the pressure during the coring. Only concentrations above the detection limits are given in Table 1.…”

Two New Reference Materials Based on Tobacco Leaves: Certification for over a Dozen of Toxic and Essential Elements

“…A graphical illustration of how the process of outlier rejection affects the overall mean is demonstrated in Figure 4 on the example of results for As in INCT-PVTL-6. This method of data processing was applied in our laboratory during previous campaigns aimed at production of CRMs [ 34 – 37 ] and also by several other producers of CRMs [ 38 – 40 ]. For the purpose of this study, two input databases for each of the candidate reference materials were evaluated.…”