The core of a snowflake is a tiny particle of dust. If the temperature is cold enough, this dust particle starts collecting tiny frozen droplets of water.
Water droplets bond with one another in a hexagonal symmetry. If the temperature and humidity are right, the snowflake will form a six-sided plate.
As the temperature slightly warms, water droplets start forming arms that grow out of the corners of the hexagon.
As the flake is blown up and down in the sky the temperature and humidity shift again and again.
Each shift causes our snowflake to crystallize in different ways as it makes its way toward earth.
Because each flake has a different journey, each carries its own singular shape.