Based on the fragmented (and altogether ambiguous) nature of this ceramic object it is impossible to determine if it is from an andiron, hearth, or oven feature. It is reddish brown and grey in color, suggesting that it had close proximity to fire and made from a coarse clay fabric. The various temper materials are visible on the surface and in the breaks of the object. The object is thick, and appears to get increasingly wider across the fragment from 34.73mm to 44.84mm. If I had to speculate I would say that this was likely part of an andiron body.