The cost for non-destructive energy dispersive x-ray fluorescence (edxrf) analysis to determine concentration estimates (in parts-per-million [ppm]) for five trace elements (rubidium [Rb], strontium [Sr], yttrium [Y], zirconium [Zr], and niobium [Nb]) is
$35 per specimen when obsidian artifacts are submitted in quantities of 11 or more. Projects with 10 or fewer specimens are charged at a rate of
$40 per sample. Specimens should be > ca. 9-10 mm in diameter and > ca. 1.5 mm thick, preferably without catalogue numbers written on the smoothest, cortex-free surface (see
What About the Physical Size of Each Specimen?).
In certain portions of North America and Mesoamerica, concentration estimates for the standard set of five trace elements will not distinguish unambiguously among obsidian sources. In these cases supplementary x-ray analyses are required to detect and measure additional elements (e.g., Fe/Mn intensity ratios, barium (Ba), titanium (Ti), manganese (Mn) and total iron [Fe2O3T]) to permit assigning an artifact to a distinctive chemical variety of obsidian ("source"). The choice of a particular supplementary analysis is governed by knowledge of which additional element, or combination of elements, provides the best discrimination among sources in any study area.
When more than 100 specimens are analyzed and reported for any project, a 10% discount will be applied to the project invoice total.
Because of tight project schedules and report deadlines, it is sometimes impossible to submit samples far enough in advance to adhere to typical laboratory processing and report preparation timelines (see
How Long Does the Analysis Take?). This, of course, is the familiar "I needed it yesterday" predicament we've all been in from time to time. When this time crunch happens GRL can arrange expedited processing of your samples, which means that your project receives IMMEDIATE attention and sample processing begins as soon as the specimens are received at the lab. Please call or email in advance to discuss this (expedited processing) option to make sure that the edxrf analysis can be completed within your time constraints. A 20% surcharge will be applied to the invoice total for expedited processing.