ICECRYSTALS
Ice crystals
Ice crystals are solid ice exhibiting atomic ordering on various length scales and include hexagonal columns, hexagonal plates, dendritic crystals, and diamond dust. The highly symmetric shapes are due to depositional growth, namely, direct deposition of water vapour onto the ice crystal. Depending on environmental temperature and humidity, ice crystals can develop from the initial hexagonal prism into numerous symmetric shapes. Possible shapes for ice crystals are columns, needles, plates and dendrites. If the crystal migrates into regions with different environmental conditions, the growth pattern may change, and the final crystal may show mixed patterns. An ...The above text is a snippet from Wikipedia: Ice crystals
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