Snow Block

Snow Blocks are found in the Snow Biome, and also dropped by all enemies of the Frost Legion. They are also created when a Snow Balla throws snowballs. These blocks, when placed, will make snow fall in the background, creating an artificial Snow Biome, which cannot be Hallowed or Corrupted.

Snow Blocks can also be crafted into Snow Bricks at a workbench, which can in turn be crafted into Snow Brick Walls

History

 * Early mention: Terraria 1.1.1 Preview! It's a Winter Wonderland! 8th December 2011