I'm starting to get a bit amazed by the prices the 1966 50 cent is reaching. Not sure if it's actually a proof coin either, just taken from a 50 cent UNC set. Scarce may be a slight overstatement ! http://cgi.ebay.com.au/2006-ROUND-5...350430643839?pt=AU_Coins2&hash=item51974b467f
Nup, it's the standard circ issue 80%. Not even a good looking coin at that. The mere fact that we put it here is probably going to drive the value even higher.
It's NOT a 1966 - it's a 2006. See http://www.australian-threepence.co...2006-50c-the-round-50c-of-1966-revisited.html - the 2006 proof set included both the 80% round 50c, and 1c and 2c coins, to celebrate 40 years of decimal currency.