[StAnDeliver]

That is a horse. There are other runic pieces of a later date that simulate the filigree design, albeit I've never seen one that looked back. Interesting the British Lion was infrequently depicted looking 'round its shoulder, much as this horse was, as a warning.

This looks like it could have capped a cloak pin or even a kilt pin.

[Red Badger]

Yes, I can see the ‘horse’ now. If you look at the ‘legs’ they extend downward and backward but aren’t black because of age or corrosion. Mentally filling in the color then you see the horse plainly..................