Decomposition Table is used for uncrafting, consuming Stardust in the process.
The table is crafted using the following recipe:
Decomposition can be started by placing a block or item (the decomposition subject) into the top slot and Stardust into the bottom slot. Amount of Stardust required depends on how many ingredients the decomposed block or item is made of, and the variety of the ingredients.
It is important to provide exact size of the stack of decomposed item - for example, in order to turn sticks back into planks, exactly 4 sticks need to be placed into the Table, not any other amount.
The amount of crafting ingredients you retrieve depends on damage and randomness. It is possible to get up to 84% ingredients back, if the item isn't damageable or is fully repaired.