Depth hoar

Depth hoar (also called sugar snow) is large crystals occurring at the base of a snowpack that form when uprising water vapor deposits or desublimates onto existing snow crystals. Depth hoar crystals are large, sparkly grains with facets that can be cup-shaped and that are up to 10 mm in diameter. Depth hoar crystals bond poorly to each other, increasing the risk for avalanches.