This whip has a staghorn or antler hook shaped handle.
There is a  a silver maker's button stamped "Callow & Son, Park Lane, London" on the heel of the horn. There is also a crown shaped iron stud or gatepusher on the top of the antler.
It has a silver collar engraved "R.F.B Jan 1 1863".
The collar has a few dents and dings.
The stock or shaft is made of blackthorn with its bark on. There is damage to a 2 inch area of the bark, but the underlying wood is still strong - please look at the images.
It has a replacement open leather keeper or loop at its end.

Dimensions : Handle : 3½" (9cm) Length (not including keeper) 22¼" (56.5cm), keeper 3" (7.5cm)
Weight 110g (4 oz)

Ref : whip1798