Professor Pogorzelski was close and Professor Olson was very far away! The small find in Alicia’s hand is indeed a piece of worked chert (very similar to the more familiar “flint”). It is stone that is worked to create very sharp edges and often, therefore, used as a tool. We don’t normally associate this type of find with a Roman site (and you might even hear that chert or flint is not found on Roman sites) because the Romans had developed technolgies to make metal tools and weapons of the highest quality. For some reason, however, we find plenty of worked chert and flint at Vindolanda with sharp edges. There is no indication of their use as they are rarely associated with anything else and do not seem to have any way to attach to a handle or any other helping mechanism. We do know the Romans generally were collectors of the past, perhaps they were a curiosity? Either way, it gets booked as a “small find” and goes down to the archaeology lab!