Thanks for your question. The value depends on the date on which you're figuring it out, because the price of gold changes daily, and also on the karat of the gold - 10k, 14k, 18k, etc.
This is described in my hub, http://hubpages.com/money/Gold-Price-Per-Pennyweig... .
Check the price of gold online. That will be in troy ounces and, depending where you look, US$. Let's pretend the price of gold is US$1000 per troy ounce.
Now sort your gold into karat weights, Weigh each group separately. Let's say you have one group of 2.281 ounces of 14K gold.
For each group, divide the karat weight by 24, then multiply that number times the weight in ounces of the gold in that karat. In our example, this works out to 1.33 troy ounces.
That is the weight of actual gold that you have, after the other metals in the alloy are taken out of the equation.
Multiply that number times the price of gold in troy ounces that you checked earlier. So in our example, the answer would be $1,330.58.
Convert that number to Australian dollars using the day's exchange rate. And that's an example of how you get your answer. :)
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