Misfire cylinder 2

[Salford boy]

Last week got a fault saying misfire in cylinder 2 car was running rough,so i decided to have a look using a scope camera,I went straight to cylinder 2 and removed spark plug the end was badly bent anyway this is what I found on top of piston scratching my head to where it came from and what is it ?

Vauxhall meriva b 1.4 turbo 2011 a14net

Any ideas/thoughts please let me know 

Thanks

[Vauxhall Owners Club]

Its hard to judge the size of it but looks like the earth electrode from a spark plug.....maybe it was replaced previously and part of it remained in the cylinder?

[Salford boy]

Here is the piece placed on top of a 10p and I  changed the sparkplugs myself roughly 10 months ago and I kept the old 1s and have checked if any bits were missing but they are fine

[Vauxhall Owners Club]

how very odd! 

its way too big for an earth electrode
it seems like the bend is too accurate for it to have been caused by the piston beating it into shape

must be something that has dropped in but from where?
Intake manifold - have seen acoustic valves and associated hardware being induced through from the inlet manifold but don't recognise that part at all.