Any body come accross anything like this before. I found three of these in the rumen of a large(103lb lardered) fallow buck. I asked around and emailed mates but no one had a clue. I finally got an answer from a vet called Peter Green who specialises in deer. They're a bit like gall stones and basically are concretions of stomach juices around a foreign body. He say's they're prolific in fallow but i've not met anybody else who's found them. Here's your chance to change that.
Some eight months ago I found all this rubbish in another big fallow buck. Comprises of polypropylene rope, silage rap and nappy liners!!!