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 GT Solar International (Nasdaq: SOLR) are having a moment in the sun today, jumping as high as 10.8% on more than double the average trading volume.

So what: It may be earnings season, but this GT Solar's jump comes from a different background: a Chinese LED systems specialist just placed a $219 million order for LED-producing tools from GT's catalog. Curiously, a $94 million order for solar-panel production tools failed to move GT's stock at all two days ago.

Now what: To put that order into perspective, GT saw $135 million of revenue in the July quarter of 2010 and $263 million to close out the calendar year – so this is a big one. One word of caution: As shown by a gloomy pricing forecast from Cree (Nasdaq: CREE), the LED market might already be oversaturated with overly-efficient manufacturing equipment. The Chinese market might stand apart from the global trend to some degree, but LED-making equipment sales could come to an abrupt halt in the near future with terrible results for GT Solar and Veeco Instruments (Nasdaq: VECO).

Interested in more info on GT Solar International? Add it to your watchlist.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insightsmakes us better investors. The Motley Fool is investors writing for investors.