Two samples
This fabric, sometimes described as made in the Eden Valley or the valley of the River Petteril, refers only to mortaria.
As a result of numerous production centres, a range of colours are represented in this group. One outstanding characteristic of many mortaria in this fabric is their hardness, and our samples are very hard and rough in feel. Their colour ranges from orange-brown (2.5YR 6/8) to maroon-brown (5YR 5/4) and those sherds with darker hues may have a lighter, redder (10R 6/8) core. Surfaces are covered with a pale orange or cream (estimated as 5YR 8/6–8/8) slip. The fracture is smooth but so highly fused as to be almost conchoidal.
The clay matrix is fine and well fired with ill-sorted and quite coarse inclusions. Within these parameters a range of variability can be seen. In our samples quartz (0.2–1.0mm, usually 0.5>), brown or red-brown iron-rich inclusions, matrix-coloured clay pellets, dark rock fragments and feldspar are all present, but proportions vary between the two samples. In one sample (i) (Plate 97a) quartz is common and dominates the inclusion suite; in the other (ii) the iron-rich grains and clay pellets are common and quartz sparse. Fine gold and silver mica is visible on the surface of both sherds. The trituration grits are ill sorted and comprise common red-brown fine-grained rock fragments (1.5–4.5mm) and sparse quartz (1.0–3.0mm).
The sample examined here was taken from variant (ii), with a fine clay matrix containing common well-sorted subangular silt-sized quartz, feldspar and mica. Sparse quartz measuring 0.1–0.4mm is also present, as are opaques or ferruginous pellets. Trituration grits consist of subangular to subrounded rock fragments, including siltstone, lava (usually altered), feldspar and a single grain of microcrystalline calcite, up to 5.0mm.
Study of mortaria recovered from excavations at Carlisle has suggested a number of sources (at present undefined) of supply in the Carlisle-Old Penrith area (Hartley 1990, 239). At least one kiln is known from Carlisle, and a number from the Petteril Valley (K Hartley, pers comm).
Carlisle Archaeological Unit
Carlisle Archaeological Unit; Tullie House Museum and Art Gallery, Carlisle
Hartley, K F, 1990 The mortaria, in A Roman, Anglian and medieval site at Blackfriars Street, Carlisle: excavations 1977–79 (M R McCarthy), 237–63