African Sigillata 1 Base 2

Identification: 
Base with low, large-diameter ring foot from medium to large open form.
Description: 

Base with low ring foot in the 12-25 cm range, slipped on both exterior and interior. 

Likely from dish forms, including African Sigillata 1 Forms 11 and 12.  Three examples have pair of grooves in floor, hence probably from African Sigillata 1 Form 11.