A guy at work, Chet, frequently stops by my office to take a break and talk about, among other things, the state of our economy. Are we going to have hyper inflation? Deflation? Should savings be put into stocks, bonds, precious metals?
I bought a few ounces of gold and silver in the late 1990s and that turns out to have been a fairly good investment. But as Chet points out, "You can't eat it."
If being able to eat it were the sole criteria for sound investing then a few tons of lentils, peas, and wheat from the farm be a good idea but my bunker can only store so many sacks before it starts getting in the way. And I'm pretty sure some of the sacks of food I sold to people worried about Y2K in 1999 (about 20,000 pounds total) are still in their closets unopened except perhaps by rodents and insects. The food stores fairly well but unless you were very careful how you stored after ten years it has noticeably degraded.
Dave Hardy points out there is an alternative to gold that is useful (I don't recommend eating it however) and which has retained it's value every bit as well as gold has for the last 136 years. When I bought my first gun the guy I bought it from pointed out that guns in good repair don't loose significant value over the years. Even that SKS you bought for $65 back in the early 1990s kept pace with inflation. Ammo too has been a good investment.
So perhaps that is Chet's answer. Instead of precious metals like gold and silver invest in steel, copper, brass and lead with a little bit of nitrocellulose thrown in.