The Nether Wart block cannot be converted back into 9 Nether Wart like how smelted ore and gem blocks can be converted back and forth. The Bone Block is also subject to this change. Since Nether Wart grows on Soul Sand like how Wheat grows on a plowed dirt block, you can compare them to wheat being able to turn into Hay bales and back.

If it is intended that the Nether Wart Block is not supposed to be a way to store Nether Wart and the Bone Block cannot be uncrafted into its original bonemeal form, delete this post immediately.