“Jewelry ice” is the name given to gemstone-like clusters of ice that gather on the Otsu Coast, near Toyokoro. This rare natural phenomenon can only be seen from mid-January until the end of February and occurs when ice from the Tokachi River flows into the Pacific Ocean and is continually smoothed over, like pebbles, by the waves. The tides then deposit the beautiful ice crystals on the shoreline for visitors to marvel over. The purity of the ice makes it highly translucent, and its appearance transforms as the sunlight changes. For an especially stellar viewing, it is recommended to head to the coast at sunrise, between 6:00 and 6:50 a.m. The morning light on the jewelry ice makes for a stunning display of colors and variation.