... Does it appear to be a piece of anything larger ...
Perhaps, perhaps not. The left and the upper edge seem to be quite straight, the remaining two seem to be damaged. We cannot tell
... or to have had
a use in its current form? ...
Again: It looks to me like a mold. There have been in antiquity
e.g. lots of crude votive
figurines in very bad style
made by the use of molds.
But because of this crudeness you cannot decide from what time it could be, this could go perhaps until the 19th century, who knows
... True, but the cruder it is, the easier to fake
as so more suspicious. Do you see anything that indicates that it is ancient? ...
It does not look really old (no stains) but also not really new (no sharp
edges). For me the question simply is undecided
. I don't have to buy it, so I can leave it like this