Researchers have developed a camera system that shoots pure snowflakes as they fall from the sky. It seems the classic picture of a snowflake is the exception rather than the rule. Those star shaped crystals only occur in 1 in 1000 flakes.
"By grabbing a series of images of the tumbling crystals—its exposure time is one-40,000th of a second, compared with about one-200th in normal photography—the camera is revealing the true shape diversity of snowflakes. Besides providing beautiful real-time 3D snowflake photographs from a ski resort in Utah, the goal is to improve weather modeling. More accurate data on how fast snowflakes fall and how their shapes interacts with radar will improve predictions of when and where storms will dump snow and how much."
http://news.sciencemag.org/sciencenow/2013/04/scienceshot-the-true-shape-of-sn.html?ref=hp