Did you know that there are a staggering 121 categories of snowflake?
The study of snowflakes is actually part of a branch of science called Crystallography. X-Rays or a transmission electron microscope are used to determine the arrangement of electrons in crystalline solids. That's any sort of crystalline solid, not just snowflakes. 2014 was actually the International Year of Crystallography.
Duke professor Adrian Bejan explains “Why Every Snowflake is Not Unique" in the video below.
They all form using the same process, in order to efficiently distribute heat. Just like rivers find the path of least resistance, snowflakes grow to get rid of heat. But it is the variables in this process that when mixed up, produce many different types of snowflake. The main variables are temperature and humidity, as shown in this graphic
The most recent scientific study done in 2013 was the one to define these 121 categories of snowflake, as well as split the classification into three sub-levels: general, intermediate, and elementary. The opening graphic shows the 39 intermediate categories, which themselves can be grouped into 8 general categorisations.
CalTech have a really good guide to different snowflakes. The fantastic graphic at the top of the page was found at Compound Chem, an awesome place to find out about the chemistry of everyday things. Plus here is another interesting article on snowflakes from the National Geographic .
