You never know what'll turn-up in the fields around here, yesterday I found this small 5 by 4 cm oyster on my early morning walk. I'm not sure if it's an actual Oyster, or a fossilised Oyster; it looks to be half and half.
In either case, what was it doing in a field sowed with Maize?
In the past I've found other fossilised bi-valves nearby; one of which was quite a large Clam-type crustacean. I suppose the whole area must have been below water at some time, so one shouldn't be too surprised to find such things.