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

What: Shares of miner Cliffs Natural Resources (NYSE:CLF) fell 12% today after announcing a reduction in planned output.

So what: The company said it will delay an expansion of an iron ore mine in Quebec and shut down some production in the U.S. because of low material prices. The announcement was actually made yesterday and the stock moved slightly higher, but upon further review, investors are seeing this as a sign of long-term weakness. Analysts at Goldman Sachs (NYSE:GS) downgraded the stock to sell and put a $25 price target on the stock.

Now what: This is one of the few mining stocks that has been able to maintain a profit, but the price pressure it too much to handle right now. Steelmaking has slowed because of a stagnant economy, and the resulting demand decrease is now hitting results. I think this stock is worth buying on the dip, because the long-term demand trends globally aren't working in its favor.

Interested in more info on Cliffs Natural? Add it to your watchlist by clicking here.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.