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 Valhi (NYSE: VHI) fell as much as 13% in a steady decline today.

So what: Yesterday after the market close, Valhi subsidiary Waste Control Specialists announced a new contract with the Tennessee Valley Authority to dispose of radioactive waste. The market cheered the news early in trading but support fell apart quickly and shares bottomed around 2 p.m. ET.

Now what: The move is a little odd, but Valhi is a relatively low-volume stock and movements can be choppy. Trading picked up throughout the day, indicating that sellers flooded the market pushing prices lower. I wouldn't get too worked up about this move because the new contract should help the company long term.

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