"Although Federation occurred in 1901, the Mint remained under...

"Although Federation occurred in 1901, the Mint remained under the jurisdiction of Britain until 1 July 1970, when it became a statutory authority of the Government of Western Australia. It is now owned by Gold Corporation which is wholly owned by the Government of Western Australia."

http://en.wikipedia.org/wiki/Perth_Mint

"Gold Corporation is a company owned by the Western Australian Government, established by the Gold Corporation Act 1987, with a mandate to operate the Perth Mint, to market Australian gold and other related activities."

http://en.wikipedia.org/wiki/Gold_Corporation


"It remained under British ownership until 1970 when control passed to the Western Australian Government, who owns it to this day.

Gold Corporation was created under its own Act of Parliament (Gold Corporation Act 1987) to take over the operations of the Mint and launch Australia’s official bullion coin program. The Australian Nugget coin was launched in 1987, and was followed by many other successful Australian legal tender bullion coin programs and numismatic and commemorative coins."
http://www.perthmint.com.au/about_us_the_perth_mint.aspx

So it does appear that Perth Mint is still own by the WA govt