For the first time petrological and geochemical analysis of the Marcus Favonius Facilis legionary tombstone at Colchester (RIB 200) was undertaken to determine its geological source. The results show the material to be identical with samples obtained from the Middle Jurassic quarries at Norroy-lès-Pont-à-Mousson of Eastern France. Rather than quarrying what became the more accessible native freestone outcrop between Humberside and Dorset, stone-masons based at Claudian Colchester were instead relying upon established continental materials from the Rhineland provinces. In this short article, petrological analysis has also been used to establish a geological link between this tombstone and the material used for funerary monuments at the pre-invasion legionary base of Facilis (and of legio XX) at Neuss.