Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

Throughout much of the past three weeks, gold-mining stocks have performed extremely well. Even when spot gold prices have fallen, investors have seemed confident that the worst was over for the mining industry. Today, though, that dynamic appeared to change, with a key report from IAMGOLD (NYSE:IAG) weighing on sentiment across the industry. Bullion ETFs were weak going into the close, with SPDR Gold Shares (NYSEMKT:GLD) falling 0.4% to reflect the $4 drop in gold prices to $1,237 per ounce, while iShares Silver (NYSEMKT:SLV) fell 0.7% as silver prices declined to $19.80 per ounce, off $0.07. Palladium gave up $2 per ounce to $745, but platinum was the lone winner, rising $7 per ounce to $1,454.

Image sources: Wikimedia Commons; Creative Commons/Armin Kubelbeck.

Part of the reason for gold's recent pullback is that the global economy has bounced back sharply from the worst years of the financial crisis. Last week's upgrading of Ireland's sovereign debt to investment-grade status marks yet another milestone for European public finance, and debt offerings there and in Spain and Portugal have gone much more smoothly than they did in the not-so-distant past. As a result, demand for gold as protection against a deeper European economic crisis has waned, and that has taken away a key underpinning of the bull market.

Yet mining company news is also weighing on gold investors today. IAMGOLD fell 12% after releasing figures on production and costs for 2013 and guidance for 2014. Despite cash costs at the lower end of anticipated ranges, IAMGOLD reported all-in sustaining costs at the upper end of previous guidance, and production levels weren't as impressive as investors had hoped to see. At the same time, IAMGOLD expects higher total cash costs, and cost-cutting measures like tightening capital spending could create further pressure on production volumes even as the company tries to concentrate on high-margin production. Those tough decisions are representative of what many players are the industry are having to make, and the overall fear sent the Market Vectors Gold Miners ETF (NYSEMKT:GDX) down 2.6% today.

Investors continue to wait to see what the Federal Reserve will do with its monetary policy at its meeting next week. Until then, gold prices will likely remain choppy, barring unforeseen events that could introduce unexpected volatility into the market.