As the gold price increases, greater efforts will be required by the wise hoarder to make sure he holds gold and silver, as opposed to something of nominal value. If this does not persuade you, I do not know what will:

http://www.tungsten-alloy.com/en/alloy11.htm

Tungsten has a density within one-quarter of one percent of gold.

To counter this, I am using the scale and Mitutoyo callipers that are accurate to 0.01 millimetre. - http://img697.imageshack.us/img697/4020/mitutoyo.jpg

Does anyone routinely take additional steps? Any experience with fakes?