Over the past three weeks, we’ve talked about several exchange-traded funds (ETFs) that have made my top-seven for 2011 list. Today, we continue with our special Alert series, and this time, the pick is literally golden.

Yet before we dig into the details of this week’s offering, let’s recap our first three ETFs. Part I in our series was the SPDR S&P Oil & Gas Exploration (XOP), while Part II was the Market Vectors Agribusiness ETF (MOO). Part III was the Technology Select Sector SPDR (XLK).

Part IV is the metals and mining stocks ETF, the Market Vectors Gold Miners ETF (GDX).

This is a fund representing gold, silver and other precious metals mining stocks. More specifically, GDX seeks performance results that replicate as closely as possible, before fees and expenses, the price and yield performance of the AMEX Gold Miners index.

The companies contained in GDX represent a who’s who of the mining industry. Top holdings include Barrick Gold Corp (ABX), Goldcorp Inc (GG), Newmont Mining Corp (NEM), AngloGold Ashanti Ltd (AU) and Kinross Gold Corp (KGC).

Not surprisingly, the recent spike in oil and the sell-off in stocks have prompted investors to move into the safe haven of gold and gold mining stocks. In fact, GDX has surged nearly 4% during the last five trading sessions. The gains in the sector show that when traders get nervous, they opt for the relative safety of gold.

If that nervousness persists, look for GDX to be a big winner in 2011.