Diamond dust

Diamond dust (ice needles, frost in the air, frost mist) A type of precipitation composed of slowly falling, very small, unbranched crystals of ice which often seem to float in the air. It may fall from a high cloud or from a cloudless sky.

Diamond Dust
Very fine, small, unbranched ice crystals. Diamond dust is so fine that it hangs in the air and is only visible as they glitter in the sun. Diamond dust can also produce a range of halo effects around the sun and moon.

Diamond Dust: Ice crystals glittered like diamonds in sun, moon or artificial light. Individual crystals appear to float in the air. Term often used to describe fall of ice crystals from apparently clear sky.

Diamond Dust
A fall of non-branched (snow crystals are branched) ice crystals in the form of needles, columns, or plates.
Differential Motion ...

Diamond dust - fine powdery ice crystals that fall in extremely cold weather, even without clouds.
Ice pellets - small hail or sleet type of precipitation.
Graupel - snow pellets - small solid white chunks of snow.

May be called "diamond dust". It is reported as "IC" in an observation and on the METAR. ICE FOG Fog that is composed of minute ice particles.

Ice Crystals (IC) A fall of unbranched (snow crystals are branched) ice crystals in the form of needles, columns, or plates. They are also referred to as Diamond Dust.

They make up cirriform clouds, frost, and ice fog. Also, they produce optical phenomena such as halos, coronas, and sun pillars. May be called "diamond dust." It is reported as "IC" in an observation and on the METAR.

in the form of irregular pellets or balls of ice more than 5 mm in diameter, falling from a cumulonimbus cloud.
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Browse Related Terms: Bergeron Process, Border Ice, BRD, Diamond dust, ...

Halo
(Lunar Halo, Solar Halo) Group of optical phenomena, in the form of rings, arcs, pillars or bright spots, produced by the refraction of reflection of light by ice crystals suspended in the atmosphere (cirriform clouds, diamond dust, etc).