Study and Application of Geochemical Reference Materials in the Institute of Geophysical and Geochemical Exploration (IGGE), China

In order to meet the needs of geochemical mapping and geochemical exploration, 125 geochemical reference materials have been successively prepared by the Institute of Geophysical and Geochemical Exploration (IGGE) since 1978. They include certified reference materials of stream sediments (GSD1-14), soils (GSS1-16; ASA 1–6, for analysis of available elements), various rocks (GSR1-6, GSR13-15), biological material (GSV1-4 and GSB 1–10), synthetic silicates (GSES I 1–11) and limestones (GSES II 1–9 for spectral analysis). They also include geochemical reference materials for ore analysis: Cu-Pb-Zn ores (GSO1-4), Cu-Pb-Zn concentrates (GSO5-7), platinum-group element (PGE) ores (GPt5-6 and GPt9-10), silver ores (GAg1-6) and geochemical reference materials for Au (GAu8-14) and PGE determination (GPt1-4, and GPt7-8). A multi-laboratory collaborative analysis scheme was adopted in the certification procedure of the IGGE. Dozens of competent laboratories with hundreds of senior analysts in China participated in the certification analysis. These samples have been supplied to more than thirty countries and more than 4000 customers from national industrial, agricultural, environmental, scientific and educational fields. Most of the geochemical reference materials are used for the calibration of measuring apparatus, evaluation of analytical methods, certification studies, quality control and laboratory accreditation programmes.     

地球化学标准物质的研制与应用

1978年以来,物化探研究所围绕我国地球化学调查和地质矿产勘查的需要,先后研制了多种地质物料的系列地球化学标准物质,包括水系沉积物、土壤(含全量和生物有效成份)、岩石、生物、光谱分析标准、多金属矿石与精矿、痕量铂族元素与铂矿石、痕量金与金矿石及银矿石标准物质,共计126个样品。具有系列性好和适用性强的特点,是我国地质测试质量体系的基本组成部分,其中GSD、GSS和GAu系列作为全国区域地球化学样品分析的量值和质量监控标准,保证了各省区不同时间、不同实验室的分析结果可以统一对比和成图。这些标准物质在我国地质矿产、冶金、农业、环境部门和科研院校中广泛应用,应用的国家达30余个。     

Determination of Trace Elements (Ag, B, Ge, Mo, Sn, W, Tl) in Reference Samples of Soils and Bottom Sediments by Atomic Emission Spectrometry: A Traceability and Fitness-for-Purpose Study

Reference samples of soils from the Institute of Applied Physics, Irkutsk (RIAP), the Institute of Geochemistry, Irkutsk (IGI) and the United States Geological Survey, Reston (USGS) were analysed with the aim of determining Ag, B, Ge, Mo, Sn, Tl and W abundances by an atomic emission method with air-stabilised D.C. arc excitation. Two series of reference samples of soils and bottom sediments, GSS-1-8 and GSD-1-12 (IGGE), were used to ensure the traceability link for the analytical results. Traceability was also demonstrated through the comparison of measured results by AES and ICP-MS methods. It is shown that the reference samples GSS-1-8 and GSD-1-12 satisfied the "fitness-for-purpose" criterion (uncertainty U of the certified value should be one-third to one-tenth the magnitude of routine laboratory data uncertainty S (S/U > 3-10)) and can be applied for calibrating AES techniques.     

岩石标准物质的研制

研制了霓霞正长岩，粗面岩，花岗闪长岩，辉长石，流纹岩及白云岩６种不同类型的岩石标准物质，对用Ｘ射线荧光光谱均匀性检验实际取样量进行了探讨，选择分析测试方法时，除采用了标准方法和长期应用的分析方法外，还采用了近年发展起来的新技术新方法，在定值中应用了多参数统计定值模式，给出了６９个元素的标准值和参考值，该批标准物质于１９９１年１月经国家技术监督局审核批准为国家一级标准物质，编号分别为ＧＢＷ０７１０９     

New Series of Soil Geochemical Reference Materials (GSS 10-16) from the Main Overburden Region in China

Seven soil geochemical certified reference materials (CRMs) GSS 10-16 recently prepared by the Institute of Geophysical and Geochemical Exploration (IGGE), are mainly used for sample analysis in geochemical surveys of the overburden region in China. Fifteen Chinese institutes and central laboratories, which operated at a high level of analytical performance analysed these samples. More than ten reliable analytical methods based on different principles of measurement were adopted, of which ICP-MS, ICP-AES and NAA were taken as the primary analytical methods. In total, 23715 determinations were carried out, 5660 average data sets were obtained, seventy two elements and components were determined and certified values of sixty nine elements and components were assigned. Rhenium concentrations were measured by isotope dilution ICP-MS in GSS-10, GSS-13, GSS-15 and GSS-16. Certified values of elements in GSS 10-16 have good precision and for 90% of these values relative uncertainties are less than 10%.     

Certified Reference Materials of Copper, Lead and Zinc (Silver) Ore Rocks and Their Concentrates (GSO 1-7)

Sulfide mineral certified reference materials GSO 1-7, recently prepared by the Institute of Geophysical and Geochemical Exploration (IGGE), were analysed by twelve laboratories. Various reliable analytical methods based on different principles were adopted and classical chemical methods were taken as the primary analytical methods, by which 5729 determinations were carried out, 1425 average data were obtained, and twenty one to twenty seven elements and components were certified.     

热水解-离子色谱法连续测定地质物料中的氟、氯和硫

研究报导了一种快速、高效和无干扰地测定地质物料中氟、氯和硫的热水解离子色谱方法。自行设计和组装了热水解装置。实验研究和选择了热水解条件、离子色谱测定的最佳工作状态,从而获得了准确可靠的结果。用本法对10个地球化学标准参考样(GSR-3,6;GSS-1,3,6,8;GSD-11,12)进行分析测定,其结果与这些标样的最佳估计值和推荐值非常一致。该方法的检出限分别为:氟6.6ppm;氯30.8ppm;硫酸根36.8ppm。方法的精密度(RSD,%)对氟含量为577ppm,氯含量为70ppm和硫酸根含量为420ppm的样品来说,分别为1.8%,12.3%和3.8%。     

DETERMINATION OF TRACE ELEMENTS IN 11 CHINESE GEOLOGICAL REFERENCE MATERIALS BY ICP-MS

More than 40 trace elements in 11 Chinese geological reference materials (stream sediments) GSD-1 to GSD-7 and GSD-9 to GSD-12 were determined by inductively coupled plasma-mass spectrometry (ICP-MS). Open acid digestions were used to prepare samples for the determination of most elements. However, for the measurement of Y, Zr and Hf, it was found necessary to use an alkali fusion in order to make fully quantitative measurements. The results obtained in this work are generally in good agreement with the recommended values from the sub-ppm level to > several hundred ppm and illustrate the versatility of the technique, particularly for some less well characterised elements.     

New Progress on Certified Reference Materials for Platinum-Group Elements: IGGE GPt-8, GPt-9 and GPt-10

Three new certified reference materials (CRM), certified for the platinum-group elements (PGE), GPt-8, GPt-9 and GPt-10 were developed based on the previous CRMs IGGE GPt-1 to GPt-7. The PGE concentration of GPt-8 is about 1 ng g^-1. GPt-9 and GPt-10 are ore samples with PGE concentrations of more than 1 μg g^-1. A multi-laboratory collaborative analysis scheme was adopted in the certification procedure, in which nine highly-experienced institutes and laboratories participated. The samples were analysed for the six platinum-group elements by nickel sulfide mini fire assay, with Te coprecipitation, and were determined by ICP-MS. Osmium was determined by isotope dilution.     

Platinum-Group Element Geochemical Certified Reference Materials (GPt1-7)

Unlike the situation for other elements, few reference materials certified for the platinum-group elements are currently available. Therefore, the GPt1-7 series of PGE geochemical CRMs, prepared by the IGGE, represent an important addition and comprise a range of matrix types, including a soil, stream sediment, Mg-rich ultramafic rock, Fe-rich ultramafic rock, platinoid ore depleted in Cu, Ni and Fe, and a chromitite. The concentration of PGE in these samples ranges over 4-5 orders of magnitude and the samples were shown to have good homogeneity as assessed by a variance test. Analytical methods based on different principles were used in sample certification, including several fire assay and wet chemical procedures used for decomposition and preconcentration. Certified values for the elements Pt, Pd, Os, Ru, Ir, Rh and Au were determined by AAS, catalytic colourimetry (COL), catalytic polarography (POL), atomic emission spectrometry (AES), ICP-MS and NAA. Recently, the GPt1-7 samples were approved as national primary CRMs by the State Bureau of Technical Supervision of China.     

Determination of Bromine and Iodine in Twenty-three Geochemical Reference Materials by ICP-MS

Trace amounts (from nanogram to microgram levels) of bromine and iodine were determined by inductively coupled plasma-mass spectrometry (ICP-MS) in twenty-three geochemical reference materials issued by the GSJ, USGS, IAEA etc. The pyrohydrolysis technique was used to separate bromine and iodine from samples analysed in the form of powder. The accuracy and precision of the experimental values were assessed by the comparative analysis of well established reference materials such as USGS AGV-1, BCR-1 and IGGE GBW07312. The measured values agreed well with reported values within a 10% error range. We also report reliable new data for these elements in these geochemical reference materials.     

GEOCHEMICAL STANDARD REFERENCE SAMPLES GSD 9–12, GSS 1–8 AND GSR 1–6

The 18 Chinese geochemical standard reference samples GSD 9-12 (stream sediments), GSS 1-8 (soils) and GSR 1-6 (rocks) were prepared after GSD 1-8 (stream sediments) for even wider and increasing needs of geology, exploration geochemistry and geochemical analysis. Usable values of 41 trace, minor and major elements of the 18 samples were published in 1984. In the following two years, efforts were concentrated on the determination of other elements, most of which are more difficult to determine accurately and hence not many data were available in the literature. At the same time, additional data on the 41 elements already evaluated were also submitted. In all, 155 234 results were available along with the 35 284 analytical data submitted. The processing of samples, the examination of sample homogeneity, the plan of collaborative analysis of the samples, and the criteria for defining the recommended values are described. The recommended or reference values of the 72 constituents, to-gether with the 35 284 analytical data of the 18 samples are published in this paper.     

Preparation and Certification of High-Grade Gold Ore Reference Materials (GAu 19-22)

Two types of gold deposit with both good homogeneity and a high-grade of gold were selected to prepare four gold ore reference materials (GAu-19,GAu-20,GAu-21 and GAu-22) by the Institute of Geophysical and Geochemical Exploration (IGGE),China.Seven laboratories participated in the certification programme. Volumetric methods for GAu19-21 and atomic absorption spectrometry for GAu-22 were used for the homogeneity testing,the coefficient of variation being found to be less than 3%.After sample digestion and preconcentration,the samples were analysed by flame atomic absorption spectrometry (AAS),colorimetry,neutron activation analysis (NAA)and volumetric analysis. The certified values for the gold concentration in GAu19-22 are 18.3 μg g -1, 32.3 μg g -1, 53.0 μg g -1 and 5.72 μg g -1,respectively.     

高温熔融研制岩石标准玻璃方法初步研究:以玄武岩为例

探索了利用高温炉合成玄武岩玻璃制作原位微区主微量元素含量分析的标准物质的实验条件.选取玄武岩标准物质GBW07105(GSR-3)进行高温熔融、淬火实验研究,获得玄武岩玻璃,为合成其他地质样品微区分析标准参考物质的研制提供了参考方法.用激光剥蚀-四极杆等离子体质谱(LA-Q-ICPMS)对样品微区46个主元素和微量元素...     

Gold, Palladium and Tellurium in South African, Chinese and Japanese Geological Reference Samples

Reliable rock reference materials for Au, Pd and Te are scarce. We report here our analytical data on these three elements in 46 NIM, IGGE and GSJ reference samples in order to accumulate analytical data on these samples.     

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.     

以多硫、多碘化合物为缓冲剂发射光谱法测定化探样品中As、Sb、Bi、Cd、Tl、In 元素

本方法建立了以多硫化合物、多碘化合物为缓冲剂(液体缓冲剂),上电极为光谱纯石墨电极、下电极为光谱纯石墨加罩电极的方式,采用控制试样法绘制工作曲线,电弧发射光谱法同时测定区域地球化学样品中As、Sb、Bi、Cd、Tl、In等6元素的测定方法。方法检出限为As1.0μg/g,Sb0.2μg/g,Bi0.1μg/g,Cd0.05μg/g,Tl0.1μg/g,In0.01μg/g;精密度(RSD,n=12)为As8.36%,Sb7.17%,Bi7.60%,Cd7.39%,Tl7.13%,In6.76%。方法用于测定国家一级标准物质GSD-1～GSD-12中As、Sb、Bi、Cd、Tl、In,测定值与标准值或参考值吻合。通过对1:50000区域地球化学调查样品中As、Sb、Bi、Cd、Tl、In实际分析,结果成图效果良好,具有简便快捷、成本低、检出限低、精度高等特点。     

GSD‐1G and MPI‐DING Reference Glasses for In Situ and Bulk Isotopic Determination

This paper contains the results of an extensive isotopic study of United States Geological Survey GSD‐1G and MPI‐DING reference glasses. Thirteen different laboratories were involved using high‐precision bulk (TIMS, MC‐ICP‐MS) and microanalytical (LA‐MC‐ICP‐MS, LA‐ICP‐MS) techniques. Detailed studies were performed to demonstrate the large‐scale and small‐scale homogeneity of the reference glasses. Together with previously published isotopic data from ten other laboratories, preliminary reference and information values as well as their uncertainties at the 95% confidence level were determined for H, O, Li, B, Si, Ca, Sr, Nd, Hf, Pb, Th and U isotopes using the recommendations of the International Association of Geoanalysts for certification of reference materials. Our results indicate that GSD‐1G and the MPI‐DING glasses are suitable reference materials for microanalytical and bulk analytical purposes.     

高温熔融研制安山岩玻璃标准物质初探

地质标准玻璃物质在激光剥蚀等离子体质谱技术应用中发挥着重要的作用,目前国内对于地质标准玻璃物质合成方法研究还较少,一定程度上限制了该技术的高精度应用。本文对国家一级安山岩粉末标准物质(GSR-2)采用高温熔融法合成安山岩玻璃标准物质(GSR-2G),探讨了熔融温度、时间、淬火方式对安山岩玻璃均一性的影响。实验确定了在熔融温度1300℃、熔融时间4 h的最佳条件下,采用液氮淬火合成的安山岩玻璃标准物质GSR-2G均一性较好,可作为微区分析的内部标准物质。利用193 nm ArF准分子激光剥蚀-四极杆等离子体质谱(LA-Q-ICPMS)分析合成的GSR-2G中35个微量元素和10个主量元素,精密度(RSD)均优于10%。GSR-2G的7Li～238U共35个微量元素,化学法分析测定值与LA-Q-ICPMS测定值的相对偏差优于10%;23Na～56Fe共10个主量元素,电子探针分析测定值与LA-Q-ICPMS测定值一致。利用LA-Q-ICPMS法分析GSR-2G中40个元素,获得的平均测定值可作为初步参考值。