Greetings Why not value it in the medium you will eventually spend it...if you are in Australia and will eventually 'spend' your gold here, surely you want to know what it is worth in A$. If you plan to use it for international exchange I guess it's a different story.
You can compare it to all the indexes you mention at http://quote.yahoo.com/m5?s=XAU&t=AUD&a=1&c=3 click on the symbol in the upper left for comparisons. Apologies if you already knew that. Cheers