Miner ETFs led the way this week as investors piled into stocks and precious metals on expectations central banks will do more to support the global economy and financial markets.

Gold is on a tear in September and traded as high as $1,745 an ounce Friday after dipping below $1,600 this summer.

Investors are looking for more quantitative easing from the Federal Reserve at next week’s meeting. The central bank may also extend its low-rate pledge or announce other easing measures.

This week, the European Central Bank expanded its bond-buying program to support sovereign debt markets.

Further monetary easing from central banks is seen as bullish for precious metals and miners, and inflationary for currencies.

Stocks also strengthened this week on central bank hopes. The S&P 500 rose 2.1% for the week in afternoon trading Friday, the Dow added 1.5% and the Nasdaq Composite gained 2.2%.

ETF Weekly Overview

The top three unleveraged ETFs this week were Market Vectors Junior Gold Miners (NYSEArca: GDX), Global X Silver Miners (NYSEArca: SIL) and iShares MSCI Spain (NYSEArca: EWP) with gains of more than 12%.

The bottom three unleveraged ETFs this week were iPath S&P 500 VIX Short Term Futures (NYSEArca: VXX), ProShares VIX Short Term Futures (NYSEArca: VIXY) and VelocityShares Long VIX Short Term (NYSEAra: VIIX) with declines of 19% or more.

The CBOE Volatility Index fell sharply this week as investors rushed into riskier assets.

In next week’s economic data, look for reports on international trade, import and export prices, producer and consumer prices, and retail sales. However, the main event will be the Fed announcement on Thursday, followed by a press conference with Ben Bernanke.