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The six ANRT rock reference samples (DR-N, UB-N, BX-N, DT-N, GS-N, FK-N) have been distributed as reference samples for nearly twenty years. All available data on trace elements in these samples are presented and evaluated. It has been possible to assign working values for nearly 40 trace elements. These samples prepared in 600 to 1300 kg quantities are expected to last for some decades to come.  相似文献   
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Since 1967–68, two mica reference samples, Biotite Mica-Fe and Phlogopite Mica-Mg, were made available to several geochemical laboratories. The analytical data reported during the past ten years by 142 geoanalysts belonging to 74 international laboratories are presented and assessed for deriving preferred values. Reaomrmended or proposed values are assigned for major, minor and several trace elements. The biotite Mica-Fe is better characterized for its chemical composition than the Phlogopite Mica-Mg. Both the samples are also proposed as geochronological standards. Because very few mica reference samples have been processed in large quantities, the international geochemiaal community is invited to contribute further useful data.  相似文献   
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The first report (1980) on the three samples, Anorthosite AN-G, Basalt BE-N and Granite MA-N resulted in the chemical characterization of major, minor and 30 trace elements. The present report confirms the validity of a great majority of these working values, in addition to presenting working values for 20 more trace elements for each sample. Only compiled data on trace elements are presented, followed by Tables of statistical parameters used as a basis for their evaluation, both statistical and subjective. A plea is made to obtain more data on platinum group elements and on other "difficult" trace elements (Au, B, Bi, Se, Te, TI, …). The three samples have been processed in 900 kg amounts and, therefore, they are likely to remain available for some decades to come. As such, it is certainly worthwhile to take pains to characterize them well for even these difficult trace elements.  相似文献   
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Three rock reference samples, Anorthosite AN-G, Basalt BE-N and Granite MA-N were analysed for their chemical composition by 122 laboratories belonging to the International Working Group "Analytical Standards of Minerals, Ores and Rocks" (IWG). 243 analysts took part in this first collaborative study which lasted only nine months, from June 1979 to March 1980. Despite this very short period, it has been possible to harvest over 6000 units of analytical data on major, minor and 53 trace elements. This excellent performance of the IWG members has rendered possible the chemical characterization of the three samples for not only the usual major and minor elements but also for 30 trace elements. This first study by the IWG Members demonstrates well their immense analytical potential and is exemplary in many respects.  相似文献   
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Third in the series of collaborative studies launched by the International Working Group "Analytical Standards of Minerals, Ores and Rocks" (IWG), the study on Ailsa Craig Granite AC-E has attracted the participation of 128 laboratories from 29 countries. Tables of compiled data, 3212 results in all, are presented with working values, recommended or proposed, for seventy major, minor and trace elements. The success of this study which lasted for only one year from the distribution of sample to the release of the present report is to be attributed entirely to the record participation of the IWG-Member laboratories.  相似文献   
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Granite GS-N and Potash Feldspar FK-N are two ANRT reference samples prepared in 1973 in 960 and 567 kg, respectively. All data reported since 1973 are compiled in this report. GS-N and FK-N are now well characterized for major and minor elements. As for trace elements, working values have been assigned for 36 elements in GS-N and for 30 elements in FK-N. We need much more data on trace elements for characterizing them better. As GS-N and FK-N are still available in large quantities and are certain to remain so for two or three decades to come, a plea is made for contribution of more data on trace elements.  相似文献   
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