It may be hard to find two snowflakes that look identical, but you can classify snow crystals according to their shapes. This is a list of different snowflake patterns.
Hexagonal plates are six-sides flat shapes. The plates may be simple hexagons or they may be patterned. Sometimes you can see a star pattern in the center of a hexagonal plate.
These shapes are more common than the simple hexagons. The term 'stellar' is applied to any snowflake shape that radiates outward, like a star. Stellar plates are hexagonal plates that have bumps or simple, unbranched arms.
Stellar dendrites are a common snowflake shape. These are the branching six-sided shapes most people associate with snowflakes.
Fernlike Stellar Dendrites
If the branches extending from a snowflake look feathery or like the fronds of a fern, then the snowflakes are categorized as fernlike stellar dendrites.
Snow sometimes occurs as fine needles. The needles may be solid, hollow, or partially hollow. Snow crystals tend to form needle shapes when the temperature is around -5°C.
Some snowflakes are six-sided columns. The columns may be short and squat or long and thin. Some columns may be capped. Sometimes (rarely) the columns are twisted. Twisted columns are also called Tsuzumi-shaped snow crystals.
Column-shaped snowflakes sometimes taper at one end, forming a bullet shape. When the bullet-shaped crystals are joined together they can form icy rosettes.
Most snowflakes are imperfect. They may have grown unevenly, broken, melted and refrozen, or had contact with other crystals.
Sometimes snow crystals come in contact with water vapor from clouds or warmer air. When the water freezes onto the original crystal it forms a coating that is known as rime. Sometimes rime appears as dots or spots on a snowflake. Sometimes rime completely covers the crystal. A crystal coated with rime is called graupel.