Fallen ornament

I spend some more time in West Linton Graveyard to document the gravestones there (if you're interested you can find pictures and text here and I was in a little walled enclosure dedicated to the Spitalhaugh family. On the ground lay this round ornament, which by the look of it has been there for quite some time as vegetation has started to grow over it.
It doesn't belong to any of the wall plaques in the enclosure and I wandered around outside for a bit to see if I could discover whence it had come. But there were no obvious gravestones that it could belong too. It has beautiful decoration, and evidently a long time as well as money was spend on it. The search will go on!