On the heels of the sub prime mortgage debacle comes word that high brow wall street banking firm Bears & Sterns (plus investors) are getting wacked with a 93% stupid tax which the American tax payer will eventually pay through the nose (yes, yes - moral hazards, blah, blah, blah).
And with gold busting through the roof at $1000+ an ounce, it may be tempting for the short sighted and nervous to throw their money into something 'more substantial'. But beware! The folks at PopSci dot Com have an interesting article on "How to Make Convincing Fake-Gold Bars", and why the masterminds behind the false-gold scandal at the Ethiopian central bank might not have gotten caught if they'd used Theo Gray's formula. 
A top-of-the-line fake gold bar should match the color, surface hardness, density, chemical, and nuclear properties of gold perfectly. To do this, you could could start with a tungsten slug about 1/8-inch smaller in each dimension than the gold bar you want, then cast a 1/16-inch layer of real pure gold all around it. This bar would feel right in the hand, it would have a dead ring when knocked as gold should, it would test right chemically, it would weigh *exactly* the right amount, and though I don't know this for sure, I think it would also pass an x-ray fluorescence scan, the 1/16" layer of pure gold being enough to stop the x-rays from reaching any tungsten. You'd pretty much have to drill it to find out it's fake.Caveat Emptor!
