About cricket ball sized, quite light and reasonably robust. Each section is hollow with a hole at the end.
No identification made yet.
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it resembles Andricus quercusstrobilanus
Can you tell if it fell from a tree, if so, which?
I looked at the link - yes, I think it could be as you suggest. It was sitting under a young Quercus robur, so that links in. I guess it's just a big, fancy gall then?
Lat/Lng: 52.562828, 0.500934
OS grid ref: TL696990
On grass under a young oak tree. Scrubby common land surrounded by farmland.