Can anyone explain this one ?
http://www.ebay.com.au/itm/Error-coin-1966-5-cent-coin-unusual-wear-pattern-/261457847519?pt=AU_Coins2&hash=item3ce01a24df&_uhb=1
Hand made post manufacture rubbish. Feel sorry for any punter that bids on this. This might be off topic and generate some negative replies but ebay should differentiate between brick and mortar business where state consumer protection law applies and everyone else where consumer protection does not apply. This would be a simple solution to cleaning this sort of thing up saying to people buyer beware.
It fails my first rule (from experience) -don't even consider bidding on any coin that only has a picture of one side. Now, my other rules don't even matter.
As for explanation: perhaps a blowtorch?
^ What he said ^