The samples recovered from the boreholes were sieved to recover artefacts. The majority of material recovered was a mixture of brick, tile and mortar. However, we also recovered:
- fish scales
- animal bones
- bird bones
- hazelnut shells
- plant material
Pottery finds were the most useful in dating deposits. Pottery is susceptible to changes in fashion, availability of clay and glazes, and to changes in technology. By looking at the fabric, shape, colour and glaze, we can date most pottery finds to within a 200 year time period. The pottery from Great Yarmouth was identified by Dr. Andrew Rogerson, of Norfolk Landscape Archaeology, and Richenda Goffin, of Suffolk County Council Archaeological Service. We recovered a large volume of architectural ceramic, such as brick, tile and daub. Although we probably recovered some of the earliest brick in the country, we cannot be certain of the date. Also, building material tends to remain in use for much longer than domestic ceramics, so cannot be used to date a layer (see the glossary entry for termini post quem).
Waterlogged wood can also be used to date deposits, through radiocarbon dating. We recovered several large pieces of wood, all with obvious tool marks. The wood and tool marks are being analysed by Dr. Caroline Cartwright, of the Department of Conservation, Documentation and Science at the British Museum. The analysis will tell us what type of wood it is, and what type of tools were used to cut and shape it. Most of the wood has been dated to the late 12th century: about the time of Richard the Lionheart and King John. One piece, from near the river, however, was dated to the late 13th century: about the time of Edward I and William Wallace.
Finds of metal objects are hard to date exactly. Certain objects can be dated roughly (cast steel, for example, post dates the invention of the Bessemer furnace in 1856). Certain types of metal object are indirect evidence of different industries. For example, fish hooks are an indication of fishing, while rove and nail closures (where the end of a nail is hammered over a type of washer called a rove) indicate boat making.
In the Great Yarmouth Archaeological Map, slags, or metalworking remains, are more interesting than iron objects. Slags can be categorised into several different types: smelting and smithing slags. Smelting slags are produced when iron ore is processed to produce iron metal, while smithing slags are produced when a blacksmith shapes iron. Some slags are reused as aggregate in building materials, whilst others, such as hammerscale are usually buried where they are produced, so are indicative of the process being carried out there. We have recovered smelting slag, smithing slag, hammerscale, and the bottoms of three blacksmiths' forges.
Some of the deposits we have processed have yielded fish and other bones. Some of these are deposited naturally, and others are dumped as rubbish. We have no way of telling unless we know they are in a man made deposit, or exhibit cut marks. Bone and shells tell us what people ate in Medieval Yarmouth - beef, pork, chicken, fish and a lot of oysters.
Click here for the Great Yarmouth bibliography.