1988 COMPILATION REPORT ON TRACE ELEMENTS IN SIX ANRT ROCK REFERENCE SAMPLES: DIORITE DR-N, SERPENTINE UB-N, BAUXITE BX-N, DISTHENE DT-N, GRANITE GS-N AND POTASH FELDSPAR FK-N

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.     

Neutron Activation Determination of The Fourteen Rare-Earth Elements In Five Rock Standards

Five geochemical reference samples. Granite GA and Basalt BK from CRPG, Diorite DR-N and Serpentine UB-N from ANRT and Andesite AGV-1 from USGS were analysed for their rare-earth element (REE) contents. All the fourteen REE were determined using neutron activation analysis. The results are presented and compared with published data.     

Report (1973–1984) on Two ANRT Geochemical Reference Samples: Granite GS-N and Potash Feldspar FK-N

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.     

SECOND REPORT (1993) ON THE FIRST THREE GIT-IWG ROCK REFERENCE SAMPLES: ANORTHOSITE FROM GREENLAND, AN-G; BASALTE D'ESSEY-LA-CÔTE, BE-N; GRANITE DE BEAUVOIR, MA-N

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.     

New REE and Trace Element Data on Two Kimberlitic Reference Materials by ICP-MS

Data on thirty-four minor and trace elements including all rare earth elements (REE) are reported for two kimberlitic international reference materials (SARM-39, MINTEK, RSA and MY-4, IGEM, Russia) by inductively coupled plasma-mass spectrometry (ICP-MS), some of them for the first time. Four digestion techniques (open acid, closed vessel acid, microwave and lithium metaborate fusion digestion) were used for the decomposition of samples for analysis by ICP-MS. Three other reference materials (USGS BHVO-1, CRPG BR-1 and ANRT UB-N) were analysed simultaneously using the same analytical methodology to assess the precision and accuracy of the determinations. The data obtained in this study compare well with working values wherever such values are available for comparison. Though open acid digestion was found to be very rapid, effective and convenient for the determination of several trace elements in kimberlitic samples, recoveries for heavy rare earth elements (HREE) were lower than the respective recoveries obtained by the other decomposition techniques used. The precision obtained was better than ± 6% RSD in the majority of cases with comparable accuracy. Chondrite-normalised plots of each RM for all the digestion techniques were smooth. The new data reported on the two kimberlitic reference materials make these samples useful for future geochemical studies of kimberlitic rocks.     

First Co-Operative Study on Four Tropical Soil Samples and One Lateritic Bauxite (Suriname) Proposed as Geochemical Reference Samples

Five samples from Suriname have been analysed for their chemical composition by 18 laboratories. The proposed reference samples are four soil samples and one lateritic bauxite. The samples were analyzed for major and minor elements as well as for 36 trace elements. More data are needed for better characterization of these samples, particularly for trace elements.     

Report (1984) on Two GIT-IWG Geochemical Reference Samples: Albite from Italy, AL-I And Iron Formation Sample from Greenland, IF-G

Two reference samples, Albite AL-I and Iron Formation sample IF-G were analysed for their chemical composition by the International Working Group "Analytical Standards of Minerals, Ores and Rocks" (GIT-IWG). AL-I was processed in 189 kg and IF-G and 760 kg. 103 GIT-IWG laboratories participated in this collaborative study along with 171 geoanalysts. This study lasted 15 months (September 1982 - December 1983) and is the second undertaken by the GIT-IWG. Over 2400 units of data were collated. As a result of this international study, the major and minor elements have been well characterized in both the samples; however, more data on trace elements will be very welcome for a better definition of trace elements, although working values have been proposed for about forty trace elements in each sample. The first and the second collaborative studies undertaken by GIT-IWG demonstrate well the immense analytical potential of the GIT-IWG.     

Reference Materials for Geochemical Studies: New Analytical Data by ICP-MS and Critical Discussion of Reference Values

Abundances of twenty four trace elements, including Y and fourteen rare earth elements (REE), are reported for eighty six geological reference materials and four proficiency testing samples. Analytical data were obtained by ICP-MS using solution nebulisation after mixed acid digestion (HF-HClO₄) under pressure. Analysed samples cover a wide range of element concentrations and mineralogical compositions, including samples for which there are few previously published data. Precision for elemental determinations in nearly 90% of the samples analysed is better than 5%. Accuracy, estimated by comparison with data from compilations is better than 6% for well characterized reference materials. Results obtained for samples that are low in trace elements are often significantly lower than compiled reference values. A critical discussion of the compiled data sets, especially for Y and the REEs, indicates that some reference values seem to be erroneous.     

Compilation Report (1966–1987) on Trace Elements in five CRPG Geochemical Reference Samples: Basalt BR; Granites, GA and GH; Micas, Biotite Mica-Fe and Phlogopite Mica-Mg

The five CRPG geochemical reference samples (BR, GA, GH, Mica-Fe and Mica-Mg) have been distributed as reference samples for more than twenty years. All data on trace elements in these samples available to the authors since their first reports have been compiled and evaluated. It has been possible to assign working values for more than forty elements in BR, GA, GH and Mica-Fe and for twenty-three elements in Mica-Mg. The samples are expected to last for another twenty years.     

1986 Values for Fifteen GSJ Rock Reference Samples, "Igneous Rock Series"

During the five-year period (April 1981 - March 1986), a series of fifteen rock reference samples, "Igneous rock series", has been prepared by the Geological Survey of Japan (GSJ). Based on the data available (published and communicated), consensus values for major, minor and trace elements have been derived; these values are presented for this second series of samples as well as for the first series of two samples, Granodiorite JG-1 and Basalt JB-1.     

Variability in the inorganic element content of U.S. coals including results of cluster analysis

Patterns of variability in trace element and major inorganic element content of 335 U.S. coal samples were investigated using the multivariate statistical techniques of principal component analysis and cluster analysis. Whole-coal basis values contain different information from ash basis values; therefore data expressed on each basis were treated separately. For each basis, major elements grouped together according to their occurrence in dominant inorganic groups in coal (aluminosilicates, sulfides, and elements organically bound or in carbonates), and relationships of trace elements to these groups were shown. Cluster analysis grouped samples based on their inorganic content. For data expressed on an ash basis, either three or four clusters were indicated. The three-cluster partition was similar to a partition into Eastern, Interior, and other (western) provinces. The partition into four clusters was more complex; is showed that samples from the Eastern and Interior provinces taken as a group can be divided into three clusters. One, characterized by low aluminosilicate and sulfur levels, contains both Interior and Eastern province samples. Thus not all Interior province samples are characterized by high levels of iron sulfide and associated elements; some are more similar to many Eastern province samples than to other Interior province samples.     

Report (1968–1978) on Two Mica Reference Samples: Biotite Mica-Fe and Phlogopite Mica-Mg

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.     

Neutron Activation Determination of Twenty-One Trace Clements, Including Rare - Earths, in Two ANRT Geochemical Reference Samples: Diorite DR-N And Granite GS-N

Results for twenty-one trace elements obtained by neutron activation analysis and high resolution Ge (Li) γ-ray spectrometry in two standard reference rocks - Diorite DR-N and Granite GS-N - distributed by the Association Rationale de la Recherche Technique (ANRT) are presented.     

A Compilation of New and Published Major and Trace Element Data for NIST SRM 610 and NIST SRM 612 Glass Reference Materials

Microanalytical trace element techniques (such as ion probe or laser ablation ICP-MS) are hampered by a lack of well characterized, homogeneous standards. Two silicate glass reference materials produced by National Institute of Standards and Technology (NIST), NIST SRM 610 and NIST SRM 612, have been shown to be homogeneous and are spiked with up to sixty one trace elements at nominal concentrations of 500 μg g-1 and 50 μg g-1 respectively. These samples (supplied as 3 mm wafers) are equivalent to NIST SRM 611 and NIST SRM 613 respectively (which are supplied as 1 mm wafers) and are becoming more widely used as potential microanalytical reference materials. NIST however, only certifies up to eight elements in these glasses. Here we have compiled concentration data from approximately sixty published works for both glasses, and have produced new analyses from our laboratories. Compilations are presented for the matrix composition of these glasses and for fifty eight trace elements. The trace element data includes all available new and published data, and summaries present the overall average and standard deviation, the range, median, geometric mean and a preferred average (which excludes all data outside ± one standard deviation of the overall average). For the elements which have been certified, there is a good agreement between the compiled averages and the NIST data. This compilation is designed to provide useful new working values for these reference materials.     

Chemical Characterisation of the USGS Reference Glasses GSA-1G, GSC-1G, GSD-1G, GSE-1G, BCR-2G, BHVO-2G and BIR-1G Using EPMA, ID-TIMS, ID-ICP-MS and LA-ICP-MS

The USGS reference glasses GSA-1G, GSC-1G, GSD-1G, GSE-1G, BCR-2G, BHVO-2G and BIR-1G were investigated by different analytical techniques. All these materials have a geological (basaltic) matrix and are therefore useful in igneous geochemistry as matrix-matched reference materials for microanalytical techniques. The new GS glasses have trace elements in groups at concentration levels of about < 0.01, 5, 50 and 500 μg g^-1. Their major element compositions have been determined by EPMA, and trace elements have been analysed by LA-ICP-MS and two isotope dilution techniques using TIMS and ICP-MS. EPMA and LA-ICP-MS analyses indicated that the USGS reference glasses are homogeneous at the μm to mm scale with respect to major (variations < 1-2%) and most trace elements (variations 1-4%). Trace element data obtained from the different analytical techniques agreed within an uncertainty of 1-5%, indicating that between method results are comparable. Therefore, the preliminary working values for the four USGS GS glasses calculated from these data have a low level of uncertainty.     

1996 COMPILATION OF ANALYTICAL DATA ON NINE GSJ GEOCHEMICAL REFERENCE SAMPLES, "SEDIMENTARY ROCK SERIES"

Analytical data compiled on nine Geological Survey of Japan (GSJ) reference samples, "Sedimentary rock series" received by February 1996 are reported. After excluding outliers and examining critically the analytical procedures employed, the data were evaluated statistically. Recommended or preferable values for fifteen major and sixty minor and trace elements are proposed.     

Determination of Rare Earth Elements, Sc, Y, Zr, Ba, Hf and Th in Geological Samples by ICP-MS after Tm Addition and Alkaline Fusion

We present a revised method for the determination of concentrations of rare earth (REE) and other trace elements (Y, Sc, Zr, Ba, Hf, Th) in geological samples. Our analytical procedure involves sample digestion using alkaline fusion (NaOH-Na₂O₂) after addition of a Tm spike, co-precipitation on iron hydroxides, and measurement by sector field-inductively coupled plasma-mass spectrometry (SF-ICP-MS). The procedure was tested successfully for various rock types (i.e., basalt, ultramafic rock, sediment, soil, granite), including rocks with low trace element abundances (sub ng g⁻¹). Results obtained for a series of nine geological reference materials (BIR-1, BCR-2, UB-N, JP-1, AC-E, MA-N, MAG-1, GSMS-2, GSS-4) are in reasonable agreement with published working values.     

Geochemistry of core sediments from Mullipallam creek,South East coast of India

The Mullipallam creek in Muthupet mangroves region is the only E-W trending coastal strip in the SE coast of India and is very important, as the mangrove acts as a barrier to natural diasters. Natural, anthropogenic signals and accumulation of elements were made by collecting sediment samples at various depths in a core. All sediments were analyzed for carbonates (CaCO₃), organic carbon (OC), major (Si, Al, Fe, Na, K, Ca, Mg, P), and trace (Mn, Cr, Cu, Ni, Co, Pb, Zn). Normalization with Al values has been done for all the major and trace elements and enrichment factors have been calculated. The calculated enrichment factors and comparison indicate that the trace metals (especially Pb) are enriched mainly due to the external (anthropogenic) activities in the land as well as in the coastal zone (Palk Strait).     

NEW REFERENCE SAMPLES OF MAGMATIC ROCKS: QUARTZ DIORITE SKD-1 AND SVIATONOSSITE SSV-1

The preparation and study of the two rock reference samples, Quartz Diorite SKD-1 and Sviatonossite SSv-1, are described, along with mineralogical and petrographic features. After its homogeneity studies, the two samples were analysed by seventy-five former USSR laboratories in the framework of an interlaboratory analytical program. The two samples have been certified respectively for 41 and 39 major, minor and trace elements; additionally, values are proposed for about 20 trace elements. The compiled data on the two samples are presented as an Appendix. Both the samples, processed in about 280 kg, form now part of the set of eight magmatic rock reference samples prepared by the Institute of Geochemistry in Irkutsk.