The basic strategy of Vanguard Precious Metals & Mining (VGPMX) is to invest at least 80% of assets in stocks of companies that explore, mine, fabricate, process or distribute metals or minerals.

The majority are in the gold, silver, platinum, diamonds and other precious metals and minerals businesses.

The fund can invest as much as 100% of assets in foreign securities. Formerly known as Gold & Precious Metals then simply Precious Metals, the fund's name was changed again in 2004.

Completely closed to new investment on June 28, 2002, it reopened with the new name, higher, $10,000 minimum and broader mandate in May 2004.

It closed again on Feb. 2, 2006. (Of course, "closed" doesn't always mean closed.)

Despite increasing diversification and a broader mission to invest in a wide variety of metals and mining stocks, this fund is no better fit for most investors now than it has been in the past. It tracks a very small market segment, is extremely volatile and can whipsaw the unprepared.

Not surprisingly then, owning this fund can really test your mettle.

When the Going Gets Rough, Investors Should Watch Out Below

Take 2006 for example. Up 47.2% in early May, the fund dropped over 26% in the following four weeks.

Or, consider the fund's MCL, or Maximum Cumulative Loss. In 2008, the fund plummeted 68.9%. Needless to say, it has a long way to go before it recovers.

That isn't to take away from manager Graham French's abilities. He takes a long view and tries to spread his bets across many companies.