Crotal bells are a favourite find for metal detectorists. They were attached to horse harnesses to warn people of the approach of horses on narrow lanes. They were in use from medieval times until the nineteenth century.
This is not a crotal bell. At a stretch it might be a budgie bell – attached to budgie harnesses to warn people of the approach of budgies on narrow lanes.
It’s probably from a dog or cat collar.
Lance Woodman 