This group is the most important of the Wroxeter mortarium fabrics.
Typical examples of this fabric are cream to white (10YR 8/3), although they are sometimes fired to shades of orange or orange-brown (5YR 6/8, 2.5YR 6/8) on the upper surface of the flange in the area of the spout. The fabric is hard with an irregular fracture and a rough feel, and the external surface is knife trimmed. A variant of this fabric (probably slightly earlier in date) may have concentric scoring on the inner surface of the vessels (K Hartley, pers comm).
A wide range of variants can be identified within this group, which form a continuum between nearly inclusionless (Plate 150c) and sandy (Plate 150a). The matrix is similar to the other variants described here with Wroxeter, compact and well fired (slightly glistening) with well-sorted inclusions, occasionally to 1.0mm. Rounded and subrounded quartz, mostly 0.2–0.3mm, and slightly finer red iron-rich grains (mostly <0.2mm) are both common. Inclusions in the largest size range tend to be red iron-rich grains. As for the vessel clay, a wide range of variability can be noted in the trituration grits. In some samples (Plate 150b) they are small and well sorted (normally 0.6–1.0mm), consisting of common quartz and sparser fragments of red or dark fine-grained rocks; elsewhere the two constituents may occur in equal proportions. Other samples contain the same range of grits but in a coarser size, such as those described for WRX OX, RS and WS.
This sample differs slightly from that described for red-slipped and white-slipped fabrics, containing somewhat finer inclusions normally not exceeding c 0.4mm. In addition to quartz (including polycrystalline) and rare flint, few other inclusions are visible apart from sparse subrounded argillaceous inclusions up to 0.45mm. A single trituration grit of altered igneous rock measuring 0.9mm is visible.