The separation of ice crystals in freshwater and brackish-water ice into individual crystals (“candles”) as the result of different melting processes between the crystals, caused by the absorption of sunlight.
Candle ice (sometimes also called “needle ice”) is a type of rotten ice that forms perpendicular to the surface of a water body. It clinks when the “candles” break up and collide as they float in the water. When ice from a larger surface melts, the formation of candle ice “progressively” increases with time, temperature and quantity of water melt runoff. This is due to the crystals’ hexagonal structure; minerals like salt, and other contaminants, can become trapped between the crystals when they first form, and melting begins at these boundaries due to the contaminants.