Going through ebay shells and found an auction, the lady was selling a three and a half inch olive she had found on the beach.
I'm sure she was being completely honest. The shell though was of the Miniacea complex from the pacific tropics. I'm willing to guess somebody bought a couple at SHell World or its ilk and deposited them on the beach to confound some poor beachcomber. Either that or we have a huge range extension.lol
Gary