A precious-metal price in Australian dollars is two prices wearing one number. The metal is dealt internationally against the United States dollar, and that figure is then carried into Australian dollars at the exchange rate of the moment. Both halves move independently, so the A$ figure can rise on a day the metal itself did nothing, purely because the Australian dollar weakened - and it can sit still through a real move in the metal that the currency happened to offset.
The unit is the troy ounce, which is not the ounce a kitchen scale measures. A troy ounce is about 31.1 grams against roughly 28.3 for the avoirdupois ounce used for groceries, so a price quoted per ounce is describing about ten per cent more metal than the word suggests. Comparing a figure here against one quoted per gram, per kilogram or per tola means converting the unit first; the numbers are not otherwise comparable.
Alongside the continuously dealt price there is a benchmark, and the two are different things. The London Bullion Market Association administers a published reference price for gold and silver, and one for platinum and palladium, each struck by auction at set times on a London business day rather than streamed. That benchmark is what contracts, funds and valuations tend to settle against, so it can differ from the last dealt figure without either being wrong.
What none of these figures is, is the price of owning any metal. A coin, a bar or a jewellery piece carries fabrication, distribution, dealer margin and often GST on top, and sells back below the quoted figure rather than at it. The gap is widest on small items and narrows with size. A price here is a reference point for what the metal is worth in the wholesale market, not a quote anybody is offering.