This seller has sold more than 10 of these coins in the last six months, always claiming not to know much about coins but having found the coin on a building site (or similar story). And he gets away with it because he says that he doesn't know if it is real or not but that there are NO RETURNS. This seller gets between $100 and $180 each for these 'fake' coins from 'hopeful' buyers. See http://www.ebay.com.au/itm/301932763789 Look at his 'feedback as a seller' to find some of the embarrassed buyers who left positive feedback before realizing their mistake, including one who bought a 'fake' mobile phone.
I don't collect this series, but at first glance it looks like the common Chinese fakes I've seen of US commemorative halves. Mushy details, teardrop-shaped dots on the obverse, disappearing detail in the crown on the reverse. Compare to images of an actual specimen here. That, and the fact that the "old building estate" has already coughed up at least ten of these coins, all in approximately the same "worn" state, even though the coin is ordinarily pretty thinly traded... except, presumably, by our Eastern friends.
Thank you jeffB.... A truly great service that you and the other more experienced "eyes" provide to expose these folks. Your second paragraph says it all... "Caveat emptor"
Anyone who buys from a sales post with this disclaimer... "THIS CROWN I FOUND ON A OLD BUILDING SITE DONT KNOW MUCH ABOUT COINS I DONT KNOW IF ITS REAL OR COUNTERFEIT OR FLAKE BUYER OWN RISK SO CHOOSE CAREFULY NO REFUNDS." ...deserves to be parted from their money. I hate con artists as much as anyone, but at least this guy's "honesty" is enough to provide a very clear and unequivocal warning to all but the most clueless buyers.