Good Friday 2018: medieval sea shells from St John’s abbey in Colchester


Last week and this week, Trust archaeology volunteers have been hard at work washing a very large quantity of sea shells from a site within the area of the precinct of St John’s abbey in Colchester. The shells were excavated from medieval rubbish-pits on a site at the Flagstaff House complex in the old Colchester garrison, where we conducted a very long-running archaeological watching brief from 2015. The watching brief was undertaken on works at the Flagstaff House complex during extensive redevelopment works (the complex is now the Arena Place residential development). This complex of listed and locally-listed buildings was once an important part of the old Colchester garrison – the commanding officers’ HQ and offices – and it is just round the corner from our HQ and the Roman circus visitor centre. The Trust has conducted a number of investigations at the Flagstaff House complex and within the area of the precinct of St John’s abbey.

We excavated tray-loads of oystershells, a quantity of whelk shells, and some bones (vertebrae) of one or more large fish during the watching brief. While the whelk shells and fish bones must represent food waste, the oystershells may represent dumps of material for the production of mortar for building on the site, within the abbey precinct, as well as the oysters having been consumed first. One of the oystershells includes a small square hole where the mother-of-pearl inside the shell has been deliberately removed for some other use such as jewellery- or button-making. We uncovered part of a medieval lime pit within the abbey precinct in 2014. We would expect the oysters to have been harvested from the River Colne.

We also retrieved medieval oystershells from the site of the friary at Grey Friars in Colchester, where we conducted another long-running watching brief, from February 2012- June 2015. We quoted an extract from the report on this watching brief (CAT Report 740) on this web-site in November 2015 at : ‘… The assemblage includes quite a lot of fish bones, which is unusual for Colchester. [The supervising archaeologist] says that the fish bones are interesting and represent more than six species of fish, ie marine species mackerel, herring, and ling; inshore marine species butterfish and rockling; and two unidentifiable species. Freshwater species were represented by eel bones. Mackerel and herring were, apparently, very popular fish for eating in the medieval period. The assemblage also produced evidence of twelve species of molluscs (over 4,000g), ie marine species (shellfish) oyster, mussel, whelk, piddock, and tellin; six species of land snails; and a freshwater pond snail (but it is probable that only the oysters, mussels and whelks represent food waste!). Oysters were a food staple in Britain for centuries …’. You can read more about Colchester oysters on this web-site at .

The site report is currently in preparation.

Trust archaeologist Mark Baister supervised the watching brief assisted by Trust excavators. All of the Trust’s archaeological investigations within the Flagstaff House complex have been funded by Taylor Wimpey.

The images show a site photo. from the watching brief at the Flagstaff House complex (above); Trust archaeologist Dr Elliott Hicks holding just one of the many trays of oyster shells from the site; the oyster shells in the tray (the featured image); four oystershells arranged to represent two shells (exterior and interior); a tray of whelk shells from the site; and vertebrae from one or more large fish from the site (roughly arranged). [image to follow]

This late medieval scallop-shell pilgrim badge was made in Spain in the 12th-16th century. It was cast in lead alloy and it is about 4.5 cm high. It is held by the British Museum. The image (below) is published online at and it is copyright the Trustees of the British Museum: it is posted here with thanks to the British Museum.
You can see an actual oystershell pilgrim souvenir online at .













It is appropriate to consider fish and shellfish today – Good Friday – because of the connections between Christianity and fish and shellfish.

























































See CAT Report 730 in our online archive for the first fieldwork project which we carried out on the site. Previous items on this web-site about our archaeological investigations and finds at the Flagstaff House complex are: , , , ,, , ,, , , , , and with a post on the lime pit at .