Vol.9 No.2 2016

Research paper : Development and utilization of geochemical reference materials (T. OKAI)−62−Synthesiology - English edition Vol.9 No.2 (2016) examinations of geological materials analysis have also been conducted, and these have contributed significantly to the chemical analysis of geological materials.2.3 Early development of global reference materialsVarious examinations and research development occurred as a result of work on these first two samples. As a result, to samples that were considered simply as standards for instrumental analysis, a new utility value, the development and evaluation of analytical methods and techniques (precision, accuracy, and level of expertise), was born. Thus, the necessity and utility of reference materials became widely acknowledged. The fact that the initial analytical values did not agree led to utility values of the reference materials. However, the first two samples were nearly exhausted because they had been used for ten years or more worldwide. Foreseeing this problem, in the 1960s, the USGS prepared six types of new samples, including G-2 (granite) to replace G-1, and reference materials were also being actively developed in many other countries. The list of the main countries (organizations) includes the USA (National Bureau of Standards, NBS), the UK (Bureau of Analyzed Samples, BAS), France (Centre de Recherches Petrographique et Geochimiques, CRPG), Canada (Nonmetallic Standards Committee Canadian Association for Applied Spectroscopy, CAAS), East Germany (Zentrales Geologisches Institut, ZGI), and Japan (GSJ) (names of organizations are as of the 1960s). The commonality among all of these organizations is that each used geological materials from its own country. Based on the list of reference materials related to geochemistry provided by Ando (1967),[1] reference materials that were issued at that time in the countries (by the organizations) listed above are summarized in Table 2. The table reveals the intentions of the various countries and organizations by the types of geological materials that were used as reference materials. The USGS focused on volcanic rocks, which are common in the bedrock of the USA, but NBS focused on materials that could be raw materials and products of the mining and manufacturing industries. Like the USGS, GSJ began their efforts with volcanic rocks.3 Developmental scenario of GSJ3.1 Basic concepts at the outset3.1.1 Background and significance of creating reference materials in JapanThe most important significance of developing geochemical materials in Japan is “elucidating the chemical compositions of domestically produced rocks at the global research level.”[6] In the 1960s, when such studies began, instrumental analysis was not common, and the wet method was mainly used. It took time to obtain chemical data, and a single analytical value was extremely important and valuable. Despite this Fig. 2 F Silicon dioxide contents and histograms for G-1 and W-1 as reported in 1951 (prepared from Fairbairn et al. (1951)[2])Peaks occur in areas greater than the mean value, showing scattering.3052.330.353472.240.37Number of analysisMeanStandard deviationNumber of analysisMeanStandard deviationSiO2 content(w/w %)SiO2 content(w/w %)FrequencyFrequencyG-1 GraniteW-1 Diabase0246810121416182002468101214161872.9872.6172.2471.8771.571.1353.0352.6852.3351.9851.6351.28CountryUSAUKFranceEast GermanyCanadaJapanOrganizationUSGSNBSBASCRPGZGICAASGSJSamplesandesite, basalt, diabase, dunite, granite, granodiorite, nepheline syenite, peridotite (in preparation)basalt, bauxite, refractory bricks, cement (five types), iron ore (two types), limestone, manganese ore, magnesite, petalite, phosphate ore, silica sand, tin ore, spodumene, zinc orerefractory bricks (two types), iron ore, manganese ore, slag (three types)basalt, biotite, granite (three types)basalt, clay shale, granite, limestonesyenite, sulfide oregranodiorite, basalt (in preparation)Table 2. International geochemical reference materials in 1967Excerpt from Ando (1967)[1] for samples published from major organization


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