Zane's Ice Spike is a Ninjago weapon mainly wielded by Zane. It is a silver axe with a large, single-bladed head (made from a Silver Blade) and a light blue gem set opposite the blade.
According to the official description, the weapon is named for the gem/spike, but the weapon itself is not made of Ice. Instead, the spike is said to be made of a rare, nearly unbreakable material similar to diamond. The carving process is described as being slow and painstaking, but contributes to the weapon's effectiveness and beauty.
It may be intended as a counterpart Lava Spike, another silver weapon with a colored gem on the opposite side of a bladed head.
Ninjago.com Description
The spike was not actually made from ice, of course. It is a rare diamond-like material that is nearly unbreakable. The process of carving the spike is very slow and painstaking. But the result is stunning!