Non destructive analysis of gold alloys using energy dispersive X-ray fluorescence analysis

AbstractApplication of a non-destructive energy-dispersive XRF technique, involving use of analytc/Compton net peak ratios, has greatly increased the analytical potential for the study of obsidians in archaeological assemblages. Contrary to reported conclusions for obsidians from the Coso Volcanic Field of southeastern California, however, the method lacks the precision associated with powdered-specimen, thin film, and other more rigorous techniques. Tests have shown that changing the orientation and/or placement of an archaeological artifact in a sample slot will produce widely divergent determinations of ppm concentrations for most specimens. These results indicate that discriminating between some chemical subsources at Coso cannot be accomplished reliably.

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Characterisation of Electroplated Gold Coatings for Dental Applications: Estimation of Thickness Using Non-Destructive Electron-Probe Microanalysis Related to Plating Time

Coatings ◽

10.3390/coatings11080874 ◽

2021 ◽

Vol 11 (8) ◽

pp. 874

Author(s):

Terry R Walton

Keyword(s):

Linear Relationship ◽

Gold Alloy ◽

Energy Dispersive ◽

Gold Alloys ◽

X Ray ◽

Complementary Method ◽

Analytical Relations ◽

Dental Applications ◽

Relationship Of ◽

Non Destructive

Objectives: This study aimed to measure non-destructively gold (Au) electrodeposited on a high-gold alloy by modulating coating time and comparing this to sputtering Au to known thicknesses. Methods: Au was electrodeposited (plated) on 11 high-gold alloy plates (A–K) at 2.8V between 20 and 220 min. Seven Au strips were sputter coated on the same alloy to known thicknesses (range 50–500 nm). Energy dispersive X-ray spectroscopy (EDS) was used to measure minimal electron energy (E0) required to penetrate Au coatings and generate x-ray signals of 1% atomic palladium (Pd) from the underlying alloy for test samples and Au strips. % Pd X-ray concentration at maximum 30 kV was also obtained. The obtained signal–thickness relationship of known Au strip thicknesses was used to calculate Au thickness on the A–K samples based on two analytical relations. Energy dispersive X-ray fluorescence spectroscopy (XRF) was used as a complementary method to ensure coating thickness estimations were accurate. Results: EDS values for all reference and unknown thicknesses were obtained and verified with XRF. Correlating these signals with the Data Analysis Software and matching with known plating times allowed estimation of Au thickness of the unknown samples (range 27–425 nm). Estimated thicknesses were shown to have a linear relationship with plating time except for samples C–D, where there was an inverted relationship. Significance: A non-destructive method for measuring electrodeposited thickness of Au on high-gold alloys related to plating time was developed and verified. There is a linear relationship to Au thickness and plating time between 20 and 220 min.

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Investigation of Obsidian by Radioisotope X-Ray Flurescence

Advances in X-ray Analysis ◽

10.1154/s0376030800017390 ◽

1983 ◽

Vol 27 ◽

pp. 459-466

Author(s):

Stephen B. Robie ◽

Ivor L. Preiss

Keyword(s):

Fluorescence Analysis ◽

Trace Element Composition ◽

Trade Routes ◽

X Ray ◽

Volcanic Material ◽

Ancient Trade ◽

Analysis Technique ◽

Destructive Analysis ◽

Non Destructive

The classification of obsidian artifacts has been receiving considerable attend of changes in obsidian trace element composition can now be identify ancient trade routes. The classification of this glassy volcanic material has been attempted using a variety of elemental analysis technique. The most successful and most widely employed method of non-destructive analysis has been that which employs X-ray fluorescence analysis (XRF); either wavelength dispersive (WDS), or energy dispersive (EDS).

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