Block party! Archaeological conservation in action
I’m Allison, a conservator, currently spending a few weeks away from PAHMA to supervise the conservation laboratory at the Mugello Valley Archaeological Project’s (MVAP) Poggio Colla field school. Poggio Colla is an Etruscan site near Florence where students can learn the fundamentals of excavation and contribute to a long-term research project investigating the ancient Etruscans. The conservation staff here works to ensure that the excavated finds are preserved for future study and appreciation. Some of the things that we do in the field lab are similar to what I do back at the museum, but others are unique to archaeological fieldwork.
For instance, archaeological conservators sometimes come to site to help excavate especially fragile items. Recently the conservation squad (myself and pre-program students Morgan Burgess, Hanna Bertoldi, Sarah Montonchaikul and Hillary Halik) helped to block lift three delicate copper alloy objects in trench PC 45.
We began by stabilizing the exposed fragmenting copper alloy in situ, applying an acrylic resin to consolidate the visible pieces. To help hold thin fragments in place, we applied a facing, or attached a piece of thin Japanese paper to the surfaces with a reversible adhesive. To get the delicate objects out of the ground in one piece- the real challenge-we pedestaled blocks of soil around the objects, and encased the entire blocks of soil surrounding the objects with plaster. The plaster created rigid walls to hold the soil and the objects in place.
Once the plaster had set, the archaeologists removed the entire plaster-encased blocks from the ground, secured them on flat supports, and delivered them to the lab. Here we can invert the blocks and carefully excavate them from the bottom up.
Taking these special measures in the field has increased the likelihood that the delicate copper alloy objects can be preserved, and has been a great learning experience for the field school students.