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For sketches of the 80 different snowflake types, see the referenced paper, which presents them taxonomically, or check out the key figures here and here.
For more Darwin Eats Cake, go here.
Magono, C., & Lee, C. W. (1966). Meteorological Classification of Natural Snow Crystals Journal of the Faculty of Science, Hokkaido University, Japan, Ser. VII, 2 (4), 321-335