Portable XRF of Archaeological Artifacts: Current Research, Potentials and Limitations

Focusing on the basic principles of mineral formation by organisms, this comprehensive volume explores questions that relate to a wide variety of fields, from biology and biochemistry, to paleontology, geology, and medical research. Preserved fossils are used to date geological deposits and archaeological artifacts. Materials scientists investigate mineralized tissues to determine the design principles used by organisms to form strong materials. Many medical problems are also associated with normal and pathological mineralization. Lowenstam, the pioneer researcher in biomineralization, and Weiner discuss the basic principles of mineral formation by organisms and compare various mineralization processes. Reference tables listing all known cases in which organisms form minerals are included.

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Possible Pitfalls in the Analysis of Minerals and Loose Materials by Portable XRF, and How to Overcome Them

Minerals ◽

10.3390/min11010033 ◽

2020 ◽

Vol 11 (1) ◽

pp. 33

Author(s):

Valérie Laperche ◽

Bruno Lemière

Keyword(s):

Fluorescence Spectroscopy ◽

Laboratory Data ◽

Data Sets ◽

Light Elements ◽

Portable Xrf ◽

X Ray ◽

Protective Films ◽

The Matrix ◽

Valuable Complement ◽

Physical Effects

Portable X-ray fluorescence spectroscopy is now widely used in almost any field of geoscience. Handheld XRF analysers are easy to use, and results are available in almost real time anywhere. However, the results do not always match laboratory analyses, and this may deter users. Rather than analytical issues, the bias often results from sample preparation differences. Instrument setup and analysis conditions need to be fully understood to avoid reporting erroneous results. The technique’s limitations must be kept in mind. We describe a number of issues and potential pitfalls observed from our experience and described in the literature. This includes the analytical mode and parameters; protective films; sample geometry and density, especially for light elements; analytical interferences between elements; physical effects of the matrix and sample condition, and more. Nevertheless, portable X-ray fluorescence spectroscopy (pXRF) results gathered with sufficient care by experienced users are both precise and reliable, if not fully accurate, and they can constitute robust data sets. Rather than being a substitute for laboratory analyses, pXRF measurements are a valuable complement to those. pXRF improves the quality and relevance of laboratory data sets.

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A New Radiocarbon Pretreatment Method for Molluscan Shell Using Density Fractionation of Carbonates in Bromoform

Radiocarbon ◽

10.1017/s0033822200046397 ◽

2010 ◽

Vol 52 (3) ◽

pp. 1301-1311 ◽

Cited By ~ 4

Author(s):

Christopher M Russo ◽

Jennifer A Tripp ◽

Katerina Douka ◽

Thomas F G Higham

Keyword(s):

Radiocarbon Dating ◽

Separation Technique ◽

Archaeological Sites ◽

Density Fractionation ◽

Pretreatment Method ◽

Density Separation ◽

Molluscan Shell ◽

Archaeological Artifacts ◽

Organic Remains

Coastal archaeological sites that lack organic remains for radiocarbon dating are often abundant sources of molluscan shells. As a substitute for materials such as bone and charcoal, shells can be analyzed with 14C dating to determine a site's age. Despite their being convenient, non-mobile archaeological artifacts, molluscan shells are plagued by several issues, including carbonate remodeling, in which aragonite in shells is converted to calcite as predicted by thermodynamics. We present here a carbonate density separation technique that addresses the issue of carbonate remodeling. Using a density fractionation with bromoform, aragonite concentrations are enriched in shells that have undergone significant remodeling. The technique has been applied to archaeological shells and has returned dates that are younger than those previously determined for the same shells.

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Boundary Morphology for Hierarchical Simplification of Archaeological Fragments

Mathematical Morphology - Theory and Applications ◽

10.1515/mathm-2020-0101 ◽

2020 ◽

Vol 4 (1) ◽

pp. 46-63

Author(s):

Hanan ElNaghy ◽

Leo Dorst

Keyword(s):

Mathematical Morphology ◽

Masking Effect ◽

Morphological Operations ◽

Fracture Surfaces ◽

Morphological Approach ◽

Archaeological Artifacts ◽

Scale Spaces ◽

Extrusion Method

AbstractWhen fitting archaeological artifacts, one would like to have a representation that simplifies fragments while preserving their complementarity. In this paper, we propose to employ the scale-spaces of mathematical morphology to hierarchically simplify potentially fitting fracture surfaces. We study the masking effect when morphological operations are applied to selected subsets of objects. Since fitting locally depends on the complementarity of fractures only, we introduce ‘Boundary Morphology’ on surfaces rather than volumes. Moreover, demonstrating the Lipschitz nature of the terracotta fractures informs our novel extrusion method to compute both closing and opening operations simultaneously. We also show that in this proposed representation the effects of abrasion and uncertainty are naturally bounded, justifying the morphological approach. This work is an extension of our contribution earlier published in the proceedings of ISMM2019 [10].

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Dating of Prehistoric Burial Mounds by 14C Analysis of Soil Organic Matter Fractions

Radiocarbon ◽

10.1017/s0033822200032434 ◽

2003 ◽

Vol 45 (1) ◽

pp. 101-112 ◽

Cited By ~ 27

Author(s):

Søren M Kristiansen ◽

Kristian Dalsgaard ◽

Mads K Holst ◽

Bent Aaby ◽

Jan Heinemeier

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Science ◽

Ams Dating ◽

Buried Soil ◽

Archaeological Artifacts ◽

Burial Mounds ◽

Organic Matter Fractions ◽

Age Estimates ◽

Organic Remains

Dating of prehistoric anthropogenic earthworks requires either excavation for archaeological artifacts or macroscopic organic matter suitable for 14C analysis. Yet, the former, in many cases, is undesirable and the latter is difficult to obtain. Here we present a soil science procedure, which has the potential to overcome these problems. It includes careful sampling of buried former soil surfaces, acid-alkali-acid fractionation of soil organic matter (SOM), and subsequent 14C AMS dating. To test the procedure, soil from one of the largest known burial mounds in Scandinavia, Hohøj, and 9 other Danish burial mounds were sampled. The 14C dates from extracted SOM fractions were compared to reference ages obtained by other methods. We show that humic acid fractions in 7 of the 10 mounds had the same age as the reference, or were, at maximum, 280 yr older than the reference ages. The best age estimates were derived from an organic-rich layer from the upper cm of buried soil or sod. Differences among SOM fraction ages probably indicate the reliability of the dating. Hohøj dated to approximately 1400 BC and, thus, was up to 500 yr older than other dated Scandinavian mounds of comparable size. The remaining investigated burial mounds were dated to between 1700 and 1250 BC. We conclude that combined sampling of buried soil surfaces, SOM fractionation, and 14C analysis allows for dating of archaeological earthworks when minimal disturbance is required, or if no macroscopic organic remains are found.

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Objective geological logging using portable XRF geochemical multi-element data at Plutonic Gold Mine, Marymia Inlier, Western Australia

Journal of Geochemical Exploration ◽

10.1016/j.gexplo.2014.03.019 ◽

2014 ◽

Vol 143 ◽

pp. 74-83 ◽

Cited By ~ 19

Author(s):

Michael F. Gazley ◽

Chelsea M. Tutt ◽

Louise A. Fisher ◽

Aaron R. Latham ◽

Guillaume Duclaux ◽

...

Keyword(s):

Western Australia ◽

Gold Mine ◽

Portable Xrf ◽

Element Data

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Metric Accuracy Evaluation of Dense Matching Algorithms in Archeological Applications

Geoinformatics FCE CTU ◽

10.14311/gi.6.34 ◽

2011 ◽

Vol 6 ◽

pp. 275-282 ◽

Cited By ~ 2

Author(s):

C. Re ◽

S. Robson ◽

R. Roncella ◽

M Hess

Keyword(s):

Laser Scanner ◽

Medium Size ◽

Accuracy Evaluation ◽

Software Packages ◽

Dense Matching ◽

Laser Scanners ◽

Surface Models ◽

University College London ◽

Archaeological Artifacts ◽

Archaeological Objects

In the cultural heritage field the recording and documentation of small and medium size objects with very detailed Digital Surface Models (DSM) is readily possible by through the use of high resolution and high precision triangulation laser scanners. 3D surface recording of archaeological objects can be easily achieved in museums; however, this type of record can be quite expensive. In many cases photogrammetry can provide a viable alternative for the generation of DSMs. The photogrammetric procedure has some benefits with respect to laser survey. The research described in this paper sets out to verify the reconstruction accuracy of DSMs of some archaeological artifacts obtained by photogrammetric survey. The experimentation has been carried out on some objects preserved in the Petrie Museum of Egyptian Archaeology at University College London (UCL). DSMs produced by two photogrammetric software packages are compared with the digital 3D model obtained by a state of the art triangulation color laser scanner. Intercomparison between the generated DSM has allowed an evaluation of metric accuracy of the photogrammetric approach applied to archaeological documentation and of precision performances of the two software packages.

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