2013 Gold Kangaroo Dimensions

If you are not happy with it, give the Perth Mint a telephone call. Out of this conversation may come the suggestion that an XRF analysis may be required. They have the equipment, and can get to the answer very quickly. They would very easily pick if it had a tungsten core. That's why they have XRF on hand, when buying bullion coins. Perth Mint in Hay Street buy as well as sell bullion coins.

I feel absolutely certain that Perth Mint would want to know if their products are being faked. I has happened to them before, and it can damage their reputation. They may well initiate an investigation, if they have not already begun one.

At LESS than the standard thickness, but at the right weight and diameter, your coin must be MORE dense than gold.
That is weird, because only some of the Pt group of metals are denser. Tungsten has about the same density as gold.

Osmium is the densest of metals, (s.g. 22.5), but would NEVER be used for coins. It is extremely poisonous.