Giant Ice Balls Form on Beach in Siberia

"Strewn for at least 11 miles on a beach in the Gulf of Ob, some of he spherical ice forms were as small as a tennis balls, while others had grown to more than a yard in diameter, reports the Siberian Times."

"Ice balls or ice boulders are made of both slush and a type of ice known as frazil ice, which occurs when loose, needle-shaped ice crystals collect in the water. When they form in calmer waters, they often look more like pancakes or flattened discs. More turbulent waters produce more spherical ice balls like those found in Russia about two weeks ago."

"As waves roll the ice crystals over and over again in the water, their spherical forms take shape. They can also gather sand if there's sand present in the water, making them appear tan in color."

"A similar phenomenon occurred in the Gulf of Finland in December 2014 and on Lake Michigan in December 2015."

https://www.wunderground.com/news/ice-balls-siberia-russia