The kitchen pottery of the empire — greywares, mortaria, and flagons.
Most Roman pottery is not samian but workhorse coarse ware: reduced grey cooking jars, black-burnished pots with lattice decoration, cream flagons, and mortaria — heavy gritted mixing bowls with a pouring spout and coarse grit studding the inner face.
Mortaria are the friendliest identification: no other vessel has that gritted interior, and many carry makers' stamps on the flange. For the rest, fabric (colour, hardness, inclusions seen in a fresh break) plus rim profile does the work — burnished lattice on grey-black fabric is a classic Romano-British signature.
Keep and record rims, bases, and handles over plain body sherds; profile is identification. Note fabric in the break, surface treatment, and sooting (a cooking pot's biography). A field that yields consistent Roman coarse ware is telling you about settlement, not just a lost pot.
Identifying pottery and ceramics
Identifying terracotta figurines