An Ice Stone was first seen inNot Caving Under Pressure!, whereSophocles's Charjabug found one while helping to fix up a cave inhabited by a group ofAlolanSandshrew, revealing that the cave was in fact an Ice Stone mine where Sandshrew gather to evolve. The leader of the Sandshrew pack, agiant Sandshrew, touched the stone and proceeded to evolve into an AlolanSandslash. Later, after exiting the cave, Charjabug was revealed to have found another Ice Stone, whichSophocles gave toLillie. She askedSnowy if it wanted to use the stone to evolve, but Snowy didn't feel ready for it yet, so Lillie decided to hold on to the stone in case Snowy ever changed its mind.
The Ice Stone was first revealed by a picture on the officialSpanish Pokémon website on October 4, 2016. However, the picture was quickly removed due to the stone not having been previously announced.