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The iron sand around Mt. Aburayama (Fukuoka, Japan), where various ancient iron‐making sites are located, was investigated to establish a research infrastructure for identification of the raw material used in the archeological iron artifacts excavated from this area. Iron sand samples were magnetically collected from the rivers flowing in this area and nearby outcrop soil. The samples were qualitatively analyzed using Mössbauer spectroscopy and x‐ray diffractometry to identify the minerals present inside them. Additionally, the elemental concentrations in these samples were determined using x‐ray fluorescence spectrometry. The iron sand samples were characterized by comparing them with those from other Japanese regions using scatter diagrams developed based on the elemental concentrations in the samples. The scatter diagrams showed clear distinctions between the iron sand samples from the Mt. Aburayama area and other Japanese regions. These diagrams may enable us to clarify the relationship between the iron sand and archeological iron artifacts found in the vicinity of Mt. Aburayama. [ABSTRACT FROM AUTHOR]

A total of 47 pottery fragments were unearthed in Hachijojima Island, part of the Izu Islands (Tokyo, Japan). Among these samples, 36 found in the Kurawa site had designs resembling pottery dating back to the Jomon period (14,000–300 BC) distributed throughout Japan's main island, Honshu; five samples from the Jomon period found in the Yubama site were "undesigned"; the rest, found in the Yaene site, were undesigned Haji pottery samples dating back to the beginning of the late Kofun period (490–549 AD). X‐ray fluorescence spectrometry (XRF) was used to determine the chemical composition (in terms of 10 major oxides and 12 minor elements) of the samples to identify their provenance, that is, local versus nonlocal. For this purpose, a portion of each pottery fragment was processed to obtain a glass bead specimen. The pottery samples were classified by multivariate statistical approaches, including principal component analysis and cluster analysis, on the basis of their chemical composition. Additionally, the XRF results were compared to geochemical data from Hachijojima Island using scatter diagrams. The data thus collected allowed the provenance of the pottery samples to be inferred. In particular, the 36 samples from the Kurawa site were concluded to have been brought to Hachijojima Island from Honshu in prehistoric times, whereas the other samples were concluded to have been manufactured locally. [ABSTRACT FROM AUTHOR]

A total of 41 pottery shards originating in the Jomon period (14000–300 BC) and Yayoi period (300 BC–250 AD) were excavated from the Shimotakabora site on Oshima Island of the Izu islands (Tokyo, Japan). X‐ray fluorescence spectrometry was used to determine the chemical composition (10 major oxides and 12 minor elements) of the potteries to identify the potteries' provenance, that is, local or nonlocal product. The calibration curves were drawn by synthetic standards prepared from a mixture of chemical reagents containing analytes, which presented good accuracy and reproducibility by analysis of the geochemical references. The pottery samples were classified by multivariate statistics such as principal component analysis and cluster analysis based on their chemical composition. Additionally, the X‐ray fluorescence results were compared with geochemical data from Oshima Island using scatter diagrams. The pottery provenance was identified by their classification. This provenance estimation indicates that 37 of the 41 potteries were brought to Oshima island from Japan's main island, Honshu, in the prehistoric age. [ABSTRACT FROM AUTHOR]

In this paper, we discuss approaches to prepare solid samples for X-ray fluorescence spectrometry (XRF). Although XRF can be used to analyze major and minor elements in various solid samples including powders and grains without dissolution techniques, to obtain reliable XRF results, the prepared sample must meet certain criteria related to homogeneity, particle size, flatness, and thickness. The conditions are defined by the analytical depth of fluorescent X-rays from analytes, and the analytical depth can be estimated from the X-ray absorption related to the energy of each X-ray and the composition and density of the sample. For example, when the sample flatness and particle size are less than the analytical depth and the sample possesses homogeneity within a depth less than the analytical depth, the XRF results are representative of the entire sample. Furthermore, an appropriate sample thickness that is larger than the analytical depth or constant can prevent changes in fluorescent X-ray intensity with variations in sample thickness. To obtain accurate and reproducible measurements, inhomogeneous solid samples must be pulverized, homogenized, and prepared as loose powder, powder pellets, or glass beads. This paper explains the approaches used to prepare solid samples for XRF analysis based on the analytical depths of fluorescent X-rays. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A low-dilution, undersized (12.5 mm diameter) glass–bead technique was developed for X-ray fluorescence determination of 34 components (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, Fe2O3, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Cs, Ba, La, Pr, Nd, Sm, Gd, Dy, Er, Yb, Hf,W, and Pb) in precious silicic samples for geochemistry and archeology. This preparation was consolidated based on the properties of the specimen, including disk formability and detachability from a small crucible, through variation of the amounts of the two samples (basaltic and granitic rocks) and releasing reagent. The specimen was prepared by fusing a mixture of 200 mg of powdered sample, 200 mg of lithium tetraborate as a flux, and 60 μl of 18.42 mass% lithium chloride solution as a releasing agent in a small platinum crucible. Calibration curves were drawn using synthetic calibration standards, which were prepared by compounding chemical reagents, such as oxides, carbonates, and diphosphates containing analytes. The calibration curves showed good linearity with correlation coefficient values greater than 0.990. Using the proposed method, we determined 34 components in five igneous rock reference samples. The results were in agreement with the recommended values, accounting for uncertainties. With this method, preparation requires only small amounts of the powdered sample and alkali flux; however, still allowing for determination of many analytes, which is advantageous when dealing with limited quantities of precious samples. The present method has potential applications in the chemical characterization of various geological and archeological samples. [ABSTRACT FROM AUTHOR]

A molded-loose-powder technique using a small powdered sample (100 mg) was developed for the X-ray fluorescence analysis of 22 components (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, Fe2O3, V, Cr, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, and Pb) in ancient pottery. This loose powder specimen was prepared by pressing the small powdered sample into a sample holder, formed from a stainless steel disk (48-mm diameter × 0.8-mm height) with a hole (11-mm diameter), by hand. Calibration standards were prepared by homogenizing chemical reagents containing these 22 analytes using the concentration ranges of 166 ancient potteries and three clay materials from Japan. The calibration curves of these benchmark mixtures exhibited a good linearity (correlation coefficient, r = 0.990-1.000), accuracy, and reproducibility compared with those of other synthesized specimens and three reference standards. The lower limits of detection were less than tens of mg kg−1 (e.g., 94 mg kg−1 for Na2O, 11 mg kg−1 for P2O5, 1.1 mg kg−1 for Rb, and 0.9 mg kg−1 for Y). Using the present method, we determined 22 components in two prehistoric potteries from Japan. The advantage of this method is that only a small amount of sample is required, which can be prepared easily and rapidly and reused for other analyses. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]