Snowflake is a snow or ice crystal, most often in the form of a six-pointed starlet or hexagonal plates. In Unicode, there are several characters of the snowflake: (U + 2744), (U + 2745), (U + 2746)
During very severe frosts (at temperatures below -30 ° C), ice crystals fall out in the form of "diamond dust" - in this case a layer of very fluffy snow consisting of thin ice needles is formed on the surface of the earth. Usually, in the course of its movement inside an ice cloud, ice crystals grow due to the direct transition of water vapor to the solid phase. How exactly this growth occurs depends on external conditions, in particular on the temperature and humidity of the air. The nature of the dependence of the scientists in general terms revealed, but could not explain it yet. Under certain conditions, ice hexahedrons grow strongly along their axis, and then snowflakes of elongated shape are formed-snowflakes-columns, snowflakes-needles. In other conditions, hexahedrons grow predominantly in directions perpendicular to their axis, and then snowflakes are formed in the form of hexagonal plates or hexagonal stars. To a falling snowflake, a drop of water can be frozen - as a result, irregular snowflakes are formed.
A closeup of the snowflakes of the Russian photographer Alexei Klyatov.