Iceblink is a Legendary Gem in Diablo III, added in Patch 2.2.0. It can only be socketed into Amulets and Rings, and drops from Greater Rift Guardians. This gem originally was Season Three-exclusive, but since this season ended, it drops for normal characters as well.
This gem adds a guaranteed Chill effect to all Cold skills that previously did not have it. Unless already better, they Chill affected enemies for 1 second, slowing them by 60%. Upgrading increases the slowdown potency of all Chill effects (not conventional Slow), to a maximum of 80%.
Due to the 80% cap on Chill Movement Speed reduction, this is one of the few gems that actually have a ranking limit, effectively becoming fully upgraded after rank 50.
Adventurers used to speak fondly of splint mail armor that would freeze their opponents in place. The sickly gem cutter, Zhong Yi Rou heard these tales and set out to create a gem that could do the same. "I'll make a few modifications all my own, yes I will" she was heard to mutter.