These fragments of Roman mosaic were recovered by NAA in 2012. They were found in York, in the western quarter of the city and inside the city walls. They came from a rubble layer directly overlying a tessellated pavement. The small fragments of the mosaic were found still adhered to their mortar bed, utilising 10mm-square tesserae in four colours (red, greenish yellow, blue-grey and white), with a small number of 20mm pieces. The greenish yellow stone was sandstone, while the blue-grey was possibly lias from the Whitby coast. The red was from fragments of brick or tile, while the white was chalk, presumably from the Yorkshire Wolds or adjacent coast. The fragments of mosaic represented five different elements. One was a band of white (at least five rows) edged by at least two rows of blue-grey. Another comprised three rows of white between grey. The most common element was part of a guilloche (interwoven strand) border, composed of single rows of tesserae, which were blue-grey, white, greenish yellow, red and blue-grey respectively. However, there was insufficient detail surviving on any fragment to determine the exact number of strands in the guilloche. Finally, there were two small triangular fragments composed of irregularly positioned 6mm to 10mm tesserae in grey and pink respectively, which appeared to be parts of a central figure rather than a border.
The mosaic of a boscampus (sea-bull) was uncovered at this site during the 19th century. This had an outer border of white with grey triangles, within which was a four-strand guilloche in the same sequence of colours as the fragments recovered from our dig. There was also a double fillet (band) of grey tesserae framing the white ground of the central decorative panel. The depiction of the boscampus was composed of grey, buff and greenish yellow sandstone, blue-grey lias, red tiles and white chalk, with an intrusive row of plum coloured slate that had been sawn rather than chisel-cut.
The fragments of mosaic found in our dig, bearing the four-colour guilloche pattern or grey and white bands, were visually and metrically identical to the elements from the border of the boscampus. Furthermore, the fragments bearing smaller tesserae in clusters of grey and pink could quite easily be accommodated within the finer detail of the boscampus. While such comparisons can be made between the two mosaics, the limited number of fragments from our excavations prevents us from determining exactly what image was represented, although it is likely to have been something equal to the boscampus image.