This is the first clipped Centenary of Federation 20c that I've seen. There's clear fish-tailing on the ELIZ on the obverse so it's a real but there's no sign of any Blakesley Effect. Perhaps the blanks are not rimmed prior to striking?
(http://www.mycoinalog.com/wp-content/uploads/2014/07/australia-2001-20c-south-australia-clipped-planchet.jpg)
Me want one!
Emma Cheezit?