Looks like the sort of o-ring that certain earrings have - mine do - but I doubt it's from them. Who knows, could be a clumsy/fiddly stoner moment with their jewelry, but
Unless your material was solventless It could be the seal some BHO extractors have where you put the nozzle of the butane can.
I'm seconding this. As inverted said, live resin and sugar are usually used when referring to solvent-based extracts.
Regardless, I would be complaining to the dispensary/company you bought the extract from, since it's contaminated product, and if it is from someone's earrings that's a biohazard
.
The other alternative is that it's from the pockety itself, but looking at images and videos I can't see anywhere that an o-ring like that would be used. I don't have one myself so I can't reliably say whether or not it would have that component, but it doesn't appear to be from the pockety. Might be wise to have a good look at all the components that make up the chamber and see if anything looks amiss, just in case.