A list of all the items affected by throwing them into Shimmer.
Shimmer is the new fluid added in the Terraria 1.4.4 Labour of Love update. It can be found rarely in newly generated worlds, or by using the Bottomless Shimmer Bucket.
Each world will have only one pool of Shimmer generate, this is a mini-biome called the Aether, it will be in the Cavern layer near the edge of the world on the same side as the jungle.
To transmute an item, it must be dropped into the liquid and fully submerged, then after a few moments will transmute and float back up to the surface. They will then hover there, emitting a slight pink glow until you collect them.
This will only work with certain items, but there are many that do work.
Firstly, it will transform crafted items back into their components, essentially uncrafting them. This can be helpful if you’ve made too many of something and wish to turn it back into its base materials.
Then there is also a list of special transformations, which will be included in full below. These allow you to get some of the newly added items, like the Rod of Harmony and the Terraformer, but it also allows some items to be turned into others. For example, it will turn a Tackle Box into High Test Fishing Line, then High Test Fishing Line will be turned into an Angler Earring, and then an Angler Earring will turn back into a Tackle Box. There are many examples of this and it is very helpful for getting the accessories you’re missing.
Shimmer can also transmute critters into Faelings, and some enemies into a shimmer version of themself. As well as that, it will turn any submerged NPCs into an alternate version of themselves. This is just a graphical change, but still quite cool nonetheless. The below image showing the NPC conversions comes courtesy of u/Gasstein on Reddit.
Special item transformations
Here is a list of all the special item transformations: