First of all, please put the
diameter in your posts, and possibly the
weight. Most times, there's no way to tell from a photo how large these
seals are, but it's an important clue to
attribution.
My guess would be late
Roman, first half 5th century. In 425-35 a similar (possibly identifcal) coin
type was introduced with a facing
Victory holding two wreaths in outstretched
hands. That
type isn't described as standing on a globe, but I think it might very well be there. This parallel might also date your seal to the joint reign of
Valentinian III and
Theodosius II.
This
type of standing
Victory was also used in early
Byzantine times, but those have different
obv. and crosses in the fields.
Regards
Gert
