Mass Spectrometric Isotope Dilution Analyses Of Barium in Geochemical Reference Samples

Twenty-four geochemical reference samples have been analysed far barium using the stable isotope dilution technique. These include five CRPG, ten ANRT, six Nimroc and two CCRMP samples together with the Tonalite from Tanzania, Duplicate analyses have been made in each case and our values for barium are believed to be accurate to approximately 3 %. In general, our results are in good agreement with the published data except for Nimroc samples where our data are consistently lower than the presently accepted values. No evidence of sample inhomogeneities was observed in the present work.     

Mass Spectrometric Isotope Dilution Determination of Cadmium in Geochemical Reference Samples

Twenty seven geochemical reference samples have been analysed for cadmium using the stable isotope dilution technique. These include four USGS, one NBS, five CRPG, eleven ANRT and six NIMROC samples. Each sample has been analysed at least in duplicate.
The four USGS samples have previously been measured in this laboratory by Rosman and De Laeter, but the present results are believed to be more accurate than the earlier data. Our results for the other twenty three samples are much lower than most of the published data. There is also evidence of cadmium inhomogeneities in some of the samples.     

Preliminary REsults of Mercury in CRPG And ANRT Rock and Mineral Standards

Nine CRPG and ANRT reference samples have been analyzed for Hg by flameless atomic absorption spectrophotometry. Preliminary data are given but mercury homogeneity has not been tested. Results of determinations on USGS samples are reported and compared with available literature values.     

Determination of Selenium in Twenty Geological Reference Materials by Neutron Activation And Inorganic Ion Exchange

Twenty geological reference samples have been analyzed for selenium using thermal neutron activation followed by radiochemical separation of ⁷⁵Se. Data are presented for 3 NBS, 11 USGS, and 6 CCRMP materials.     

Determination of Selenium in Twenty-Eight Geological Reference Materials by Atomic Absorption Spectrometry

Twenty-eight geological reference samples have been analysed for selenium using atomic absorption spectrometry with hydride generation and quartz cell atomizer and/or with solvent extraction and carbon tube atomizer. Data are presented for 5 CCRMP, 6 USGS, 3 NBS, 6 NIM and 8 GSJ reference materials.     

RARE EARTH ELEMENT CONCENTRATIONS IN USGS AND CCRMP IGNEOUS ROCK STANDARDS DETERMINED BY HIGH PERFORMANCE ION CHROMATOGRAPHY

Eleven rare earth elements (REE) have been determined in ten USGS and two CCRMP igneous rock standards using high performance ion chromatography. Duplicate analyses of two or more separately prepared aliquots of each sample were undertaken; reproducibility was better than 5% for each of the REE. In most cases, the results compare closely with published REE values for those samples for which the REE are well characterised. Where the results for individual elements are in disagreement with published data, the more erratic patterns yielded by the earlier data when plotted on chondrite-normalised REE diagrams suggest that values determined in this study are of greater accuracy.     

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.     

Determination of Boron in 35 International Geochemical Reference Materials by Thermal Neutron Capture Prompt Gamma-ray Spectrometry

Concentrations of boron in 35 silicate reference materials are measured by thermal neutron capture gamma-ray spectrometry. Results are compared for NBS, USGS, and CCRMP reference materials with values from the literature. The use of two prompt gamma facilities at Los Alamos are discussed.     

Determination of Fluorine and Total Water in Thirty-Three International Geochemical Reference Samples

Thirty-three reference samples from the United States Geological Survey (USGS), Centre de Recherches Pétrographiques et Géochimiques (CRPG, France), Association Rationale de la Recherche Technique (ANRT, France), National Institute for Metallurgy (NIM, South Africa), Geotechnic Institute (GI, Austria), Mineralogical Institute of Basel and Bern (Switzerland), Zentrales Geolo-gisahes Institut (ZG1, DDR) and from the For-chungeinstitut der Zementinduatrie (Düsseldorf, GDF) were analysed for their fluorine and total water content. Fluorine was determined, after pyrohydrolysis, with an ion-selective electrode. Total water was determined, after pyrolysis, by Karl-Fischer titration. Our values, five determinations on each sample, are compared with the preferred values.     

Instrumental Neutron Activation Analysis by Collecting Only One Spectrum: Results For International Geochemical Reference Samples

Instrumental neutron activation analysis of rocks and minerals is currently done on basis of collecting 2 or 3 energy spectra. We have found that, by collecting one spectrum one week after irradiation, satisfactory results for the USGS and CRPG geochemical reference samples can be obtained.     

DISTRIBUTION OF CCRMP, NIST, AND USGS REFERENCE MATERIAL DATA IN THE LITERATURE (1950 - 1989)

Publication patterns of CCRMP, NIST, and USGS reference materials are traced over the past 40 years by literature source, analytical method employed, and constituents measured. This is the first update to our 1987 paper which covered the period 1951 - 1985.     

Compilation of Boron Concentration Data for NBS, USGS and CCRMP Reference Materials

Boron concentration data on 69 different biological, coal and geological reference materials issued by NBS, USGS and CCRMP have been collected from 1951-1986. Data from 135 journal articles and technical reports are included. These data are summarized in consensus (mean) values with uncertainties expressed as pm one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables.     

Instrumental Thermal Neutron Activation Determination of 20 Elements in Nineteen Silicate Reference Materials

Elemental concentrations of Al, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, Mn, Na, Rb, Sb, Sc, Ta, Th, Ti and V have been measured in 11 USGS, 6 CCRMP and 2 NBS reference materials by instrumental thermal neutron activation analysis. The results are compared with recent consensus and agency values.     

Distribution of NBS, USGS and CCRMP Reference Material Data in the Literature (1951-1985)

Publication patterns of NBS, USGS and CCRMP reference materials data are traced over the past 35 years by literature source, analytical methods employed, and constituents measured.     

Some Trace-Element Contents of Biotite, Btt-1, and Hornblende, Hbl-I, by Semiquantitative Spectrographic Analysis and by Instrumental Neutron Activation Analysis

Some trace-element contents of U.S. Geological Survey (USGS) samples, biotite Btt-1 and hornblende Hbl-1, were determined by both computerized semi-quantitative spectrographic analysis and instrumental neutron activation analysis. An equal number of portions of the Centre de Recherches Pétrographiques et Géochimiques (CRPG) samples, biotite Mica-Fe and phlogopite Mica-Mg, were randomized with portions of the USGS samples and analyzed simultaneously to allow direct comparisons of trace elements in the biotites. Mica-Fe has concentrations of Cs, Hf, Ta and Zn that are greater by factors of 3 or more than those in Btt- 1. Although the Co contents of the two biotites are nearly equal, the amounts of Cr, Sc, La and the rare earth elements are significantly greater in Btt-1. Mica-Mg contains larger amounts of Cs and Rb than does Hbl-1, whereas the Cr content of Hbl-1 is 15 times that of Mica-Mg. Btt-1 and Hbl-1 may be useful as comparison samples for the analysis of biotites and hornblendes after other data are available.     

1983 Compilation of Elemental Concentration Data for Samples SO-1 to SO-4

Concentration data for as many as 72 constituents in the four Canadian Certified Reference Materials Project (CCRMP) soil samples have been collected from journal articles and technical reports published since these soil standards were issued in 1978. These data are summarized into mean +/- one standard deviation values and compared with available certification data from CCRMP. All literature data located or calculated are presented in the appendices.     

Determination of Indium and Tellurium in Fifty Nine Geological Reference Materials by Solvent Extraction and Graphite Furnace Atomic Absorption Spectrometry

The indium (In) and tellurium (Te) contents of fifty nine geological reference materials, issued by several reference material producers (USGS, CRPG, ANRT, GIT-IWG and GSJ) have been determined by graphite furnace atomic absorption spectrometry, after aqua regia and HF digestion, and extraction of iodide complexes with trioctylmethylammonium (TOMA) - metyl isobutyl ketone (MIBK). Although the interferences from most elements can be minimised by the addition of palladium solution as the matrix modifier, large concentrations of Bi, Cu, Pb or Sn suppress the absorbance of In and/or Te. Samples for analysis were therefore restricted to those in which the concentrations of these interfering elements did not cause a significant interference. The limit of detection was 0.2 ng g⁻¹ In and Te for 1 g test portions. The agreement between the reported results and published data is satisfactory.     

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.     

Atomic Absorption Determination of Ultratrace Elements in Geological Materials by Vapor. Hydride-Forming Techniques. I. Mercury

A method is described for the determination of mercury at nanogram levels in geological materials by flameless atomic absorption spectroscopy after metal vapor generation. Mercury is converted to a soluble form by H₂SO₄-HNO₃ attack in a teflon bomb at 180°C for 90 minutes. Metal Hg vapor is obtained by reaction with combined NaBH₄-NaOH using the Perkin-Elmer MHS - 10 hydride system and determined at room temperature. Mercury can be easily determined in most silicate materials. The sensitivity of the method depends essentially on the purity of the reagents and contaminations during handling rather than on instrumental capabilities. A detection limit of about 10 ng/g Hg for 0.5 g samples has been achieved with the use of normal "suprapure" reagents. Mercury contents on some USGS, CRPG and ANRT reference samples are reported.     

An Inter-Laboratory Assessment of the Thorium Isotopic Composition of Synthetic and Rock Reference Materials

We present a concerted international effort to cross-calibrate five synthetic Th isotope reference materials (UCSC Th "A", OU Th "U", WUN, IRMM-35 and IRMM-36), and six rock reference materials (UCSC TML, Icelandic ATHO, USGS BCR-2, USGS W-2, USGS BHVO-2, LV18) using multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS). We then compare our new values with a compilation of literature mass spectrometric data for these reference materials and derive recommended "consensus"²³⁰Th/²³²Th values for each. We also present isotope dilution U and Th concentration data for four rock reference materials (UCSC TML, Icelandic ATHO, USGS BCR-2, USGS W-2).