The You Had Me hitmaker was among the star guests at the Rocket Man's 2005 marriage to David Furnish, and she was offered some sparkling gems to complement her dress.
Stone later hit the dance floor with pals but forgot she was wearing borrowed jewellery - and she ended up crawling around the venue on all fours after one of the diamond earrings fell out.
She tells British magazine Event, "At Elton John's wedding I was put in diamonds. I didn't even ask for them, but you can't kick up a fuss and say no, so you just smile and let them do it.
"And then I'm there with these b**ody diamonds on and I was on the dance floor dancing my little butt off having a laugh and then I felt my ears and one of them was gone. So then I'm scrabbling on the floor under all these people's feet looking a right idiot trying to find this diamond, feeling sick because if I don't find it then I have to pay for it.
"Thank God I did (find it). But for me it's just way too stressful; I'd rather wear a £2 pair I've got at home."