[LeoTDB69]

Shapes like this are quite common. Hail forming in clouds can melt and refreeze multiple times into many unusual shapes.

https://www.wqad.com/article/weather/zombie-hail-what-causes-odd-hail-shapes/526-794d2c5d-0cdf-4791-a072-2af569c0aef6

[clearcarbon]

"Shapes like this are quite common. Hail forming in clouds can melt and refreeze multiple times into many unusual shapes."

I'd guess that a larger volume or surface area vs. mass allows them to stay aloft longer and get larger.