Crossing the Borders: New Methods and Techniques in the Study of Archaeological Materials from the Caribbean

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study were free from visible cracks, lustrous, and either white or covered by only a
thin and easily removed outer layer of dull, yellowed enamel, with white enamel
underneath. Four enamel samples from rice rats were included in the study to determine
the local isotope signature. Rice rat enamel was sampled from mandibles
of four rice rats, collected from midden deposits at Anse à la Gourde that were
contemporary with the human burials. Soil samples of at least 500 g have been collected
from the fill of the graves.
Methods
Enamel Samples
Teeth were washed in water to remove dust and residual soil. Tooth enamel was
sampled using a steel ball- shaped microdrill. The outer layer of enamel and any
adhering dirt was first removed using the drill until only white enamel was visible.
The drill was then cleaned in 1N HCl and Milli- Q water and used to drill a hole of
ca. 1 mm in diameter and up to ca. 1 mm depth. The teeth were usually sampled
on the buccal or lingual side of the enamel crown, but occasionally on the occlusal
surface if it was smooth. Approximately 1 mg of enamel was gathered per tooth.
The enamel powder was collected in glass sample containers that had been precleaned
with 6N HCl and Milli- Q water. Rice rat teeth were halved, fixed in resin,
and drilled with a diamond- tipped drill. Again ca. 1 mg of enamel was collected.
Soil Samples
The soil samples were oven dried, crushed in a jaw crusher, and homogenized.
An aliquot (ca. 10 percent wt) of each was taken and powdered in an agate planetary
ball mill. Five g of this powder is used to produce a tablet for X- ray fluorescence
(XRF) measurement, which determines, among others, the elemental abundance
of strontium. Based on these data, approximately 2 g of powdered sample
was separated to be used for Sr- Nd- Pb isotope analysis. In a clean room this aliquot
was transferred to an acid- cleaned Teflon beaker and precisely weighed. The
sample was then treated with 6 ml 40 percent distilled HF and 1 ml concentrated
distilled HN03 for two days for destruction of silicate bonds, after which it was
dried down. The sample was then dissolved in ~25 ml 6N HCl to produce a stock
solution from which an aliquot is separated containing approximately 200 ng
strontium, calculated based on XRF data. This aliquot was dried, and 2–3 drops of
concentrated HN03 were then added and dried, twice.
Strontium Separation
Strontium separation was performed in a clean room under class 100 air. The
enamel was suspended in Milli- Q water, transferred to an acid- cleaned Teflon beaker,
dried down, and dissolved in 1N HCl, then dried down again. The sample was
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