For each bone, a few grams were taken with a polyester tool (Retsch GmbH, Germany). Due to the poor preservation state of some bones, the use of a mortar and pestle was enough to reduce them to powder. For the more intact bones the samples were powdered in a polyester mill (Retsch GmbH, Germany). In both cases the resulting bone powder was pressed into pellets 15 mm in diameter, by a 10 t manual hydraulic press from Specac. There was no further chemical treatment or additive to the samples.
For each bone n¼9 pellets were made to minimize effects of inhomogeneity. Each pellet, with a thickness of about 1 mm, was glued (heptane mixture) on a Mylar film, fixed into a slide mount and placed on the sample holder (50 mm x 50 mm) in front of the X-ray beam for the element determination.
The remains of two burial shrouds were also analyzed by this instrument but no further treatment was needed, a small piece was placed in front of the beam and the X-ray spectrum was obtained. For the bones of interest transversal sections, around 1 mm thick, were obtained using a microtome equipped with a diamond saw (Buehler Isomet 1000, USA). The resulting sample slice would then be placed inside the XRF chamber on a table attached to a XY translatable stage and directly exposed to the X-ray microbeam to perform the elemental mappings. For each bone of interest one map was acquired.
For each bone n¼9 pellets were made to minimize effects of inhomogeneity. Each pellet, with a thickness of about 1 mm, was glued (heptane mixture) on a Mylar film, fixed into a slide mount and placed on the sample holder (50 mm x 50 mm) in front of the X-ray beam for the element determination.
The remains of two burial shrouds were also analyzed by this instrument but no further treatment was needed, a small piece was placed in front of the beam and the X-ray spectrum was obtained. For the bones of interest transversal sections, around 1 mm thick, were obtained using a microtome equipped with a diamond saw (Buehler Isomet 1000, USA). The resulting sample slice would then be placed inside the XRF chamber on a table attached to a XY translatable stage and directly exposed to the X-ray microbeam to perform the elemental mappings. For each bone of interest one map was acquired.