From the blog "Sandbox Update Notes"
+ Added small and large rocks which generate across the surface (will be covered in snow or moss at times depending on biome)
+ Added Snowball (dropped when breaking snow, and can be obtained by shoveling snowy rocks)
+ Added Sandstone item
+ Added small bushes which generate on grassy surfaces (can also have snow overlay), dropping wood when broken
+ Added Char biome (name subject to change), a volcanic biome
+ Added Ash tile
+ Added Copper Tools (Axe, Hammer, Hoe, Pickaxe, Shovel S