Snow are able to grow to hundreds of micrometers or millimeters in size at the expense of the water droplets by the Wegener–Bergeron–Findeisen process. The corresponding depletion of water vapor causes the ice crystals to grow at the droplets' expense. These large crystals are an efficient source of precipitation, since they fall through the atmosphere due to their mass, and may collide and stick together in clusters, or aggregates. These aggregates are snowflakes, and are usually the type of ice particle that falls to the ground. Although the ice is clear, scattering of light by the crystal facets and hollows/imperfections mean
Granular ice Granular ice Granular ice is one of the types of ice commonly referred to as Flake ice. Made in a tall, thin, vertical drum or 'freezing unit' with an auger running axially in the centre. A water level is set in the bottom of the drum by gravity and as ice crystals begin to form, the auger carries them up the drum where they are compressed and further frozen until they are ejected from the top as 'flakes'. By changing the geometry of the auger and introducing 'ice breakers' into the ejection arrangement, the size and appearance of the ice