Discerning geological and geographical sources of Belgian Upper Paleolithic fluorites by rare earth elements and Sr-isotopic geochemistry

Fragments of fluorite (CaF2) have been found at five Belgian Upper Paleolithic sites (Spy, Chaleux, Trou Magritte, Trou du Frontal and Verlaine caves), primarily of Magdalenian age. These sites are located in a large geographical area. The aim of this study is to isolate one or more primary sources where the mineral could have been quarried prehistorically, and hence try to deduce if time and effort were put into obtaining it, or if it was simply a useful nearby raw material. In order to achieve this objective, isotopic 87Sr/86Sr and REE ratios are used. A total of four archaeological samples from the Chaleux, Spy and Trou Magritte sites along with geological samples were analyzed (new results and data from the literature), obtained from two distinct stratigraphical units in Belgium: the Givetian limestones (mainly from the Calestian Band), and the Dinantian limestones.Results show a single geological and geographical origin for the archaeological material: the silicified Givetian limestones of the Calestian Band near Givet (France). When looking at the 440 g of fluorite recovered at Chaleux cave, Chaleux could perhaps have had a central role in the distribution of fluorite in the region. Chaleux and Givet are both situated on the banks of the Meuse river, relatively proximal to one another, while the Spy cave is more distant from Givet and do not share the same river trajectory. We propose as possible that fluorite was quarried at Givet and taken to Chaleux via the Meuse river to be further distributed from there. The second scenario assumes that fluorite is transported directly from Givet to all the other studied sites.

All Belgian Upper Paleolithic archaeological fluorites have a single origin.
► Silicified Givetian limestones from Givet (France) are the source of the material.
► REEs combined with strontium isotopes are useful for provenance determination.
► We report 2 probable scenarios of fluorite distribution.