The excavations at Binchester Roman Fort have wrapped up and the time is nigh for the post-excavation processing. The project has run for seven years and unearthed some fascinating objects, as well as a wealth of auxiliary data from more common artefacts.
At the conservation department, we are currently helping to process this post-excavation collection by cleaning and consolidating the copper alloy coins, and learning about copper chemistry and conservation processes along the way. We are using an appropriate solvent solution for metals with a few drops of a detergent to remove the built up dirt and porous corrosion on the exterior the coins in order to see what might have survived underneath. Mechanical cleaning methods can help to remove the more stubborn corrosion layers.
Through this process we have discovered some fine examples of late Roman era coins that will aid in the final interpretation of the Binchester dig site. Some coins have lost most of their design, but others have survived very well in the record and show crisp portraits and inscriptions that numismatists can use to date the coin and fit it into a wider typology. We have even discovered the occasional silver alloy coin, which makes for a pleasant surprise while swabbing away the mud! Once cleaned, we consolidate the coins using an appropriate solution for metal objects which aims to limit any further corrosion, so the collection can be stored and maintained under the right conditions for future studies with little fear of information loss.
Amongst the coins we’ve cleaned, we have found identifiable portraits of Roman emperors, Latin inscriptions, and the occasional depiction of Romulus and Remus being raised by the she-wolf. Half the fun and interest of the cleaning and consolidating process comes from trying to see what can be deciphered from these corroded coins and speculating on their nature and origin. It’s a great way to hone one’s skills of deduction and interpretation, as well as learning how to clean and take care of historic objects.
Chris.