Monday brought investors a mixed bag of news, with the positive of no dramatic escalation in the Ukrainian crisis but the negative of extremely weak export activity from China. The broad stock market ended the day in a draw, with very modest declines for the S&P 500 and Nasdaq Composite. But voxeljet (NASDAQ:VJET), Walter Energy (OTC:WLTGQ), and E-Commerce China Dangdang (NYSE:DANG) posted substantial losses despite the flat day for markets generally.

3-D printing company voxeljet fell 6% on a terrible day for 3-D printing stocks generally, with 3D Systems (NYSE:DDD) and ExOne (NASDAQ:XONE) both falling 5% in sympathy. The culprit was a cover story in this week's Barron's that told investors to beware of the sector, with the story suggesting that the highly publicized stocks in the sector face tough competition from companies that aren't yet trading publicly, making voxeljet, 3D Systems, and ExOne less compelling than they might otherwise be. Yet investors need to understand that for stocks trading at such lofty valuations based on current business prospects, voxeljet and other stocks in the sector will be extremely volatile until the industry develops more fully. Only at that point will it become clear which companies will prove to be the winners in 3-D printing.

Walter Energy dropped almost 10% as the coal-mining company said that it would have to try to change the terms of its term-loan financing. Currently, the lending arrangement requires Walter Energy to make payments on a second term loan before refinancing the first, but Walter Energy would prefer to conserve cash and only modify the first existing loan. If approved, the move will help Walter deal with ballooning levels of debt compared to its cash flow.

Dangdang declined 11%, due largely to negative sentiment stemming from the poor Chinese export numbers and their potential impact on levels of e-commerce activity in China. Even though Tencent Holdings agreed to take a 15% stake in e-commerce site prior to its planned U.S. IPO, Dangdang and its peers are going through the same weeding-out process that hit U.S. Internet stocks in the early 2000s. Dangdang will have to work hard to find ways to differentiate itself from its peers and stay strong even if the e-commerce environment in China gets worse.

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