Ice weapons are made of ice, typically split off the Ice Dagger in the Northern Kingdoms. The blades vary, from swords to scimitars to daggers to even ice splinters for tinier owls like Elf Owls and Pygmies.These splinters are lauched at an enemy, often aimed at the eye, and are even sharper than the swords.The ice weapons were buried to keep them from melting and to perserve their sharpness. A properly cared for weapon could even withstand fire.
Ice weapons were at first used in the Northern Kingdoms. They were ancient weapons, dating back to the time before King Hoole and continued use even after the reign of Coryn. They didn't come to the Southern Kingdoms until the reign of Boron and Barran. There was no need to keep the weapons, because they melted more easily in the warm southern climate and it was too much trouble to keep them safe. And the invention of Theo's battle claws made them unecessary for the Southern Kingdom owls. They only reappeared when the band brought them back during the Battle of the Burning. Note: I may've up a few