1. A aluminum ferring stores their identity in a metalmind
2. A Nicrosil compounder compounds Nicrosil, creating dozens of Nicrosilminds full of Nicrosil Feruchemy while tapping the duralumin ferring’s Identity, so these metalminds are now keyed to the aluminum ferring.
3. The compounder also uses the same method to store Nicrosil Allomancy
4. The aluminum ferring then taps the Nicrosil compounder’s metalminds, then immediately re-stores both the Allomancy and Feruchemy while storing Identity, creating Unkeyed Nicrosilminds. I imagine you could also do this with copper, removing the memories of your coppermind, then immediately restoring them to create an unkeyed version
5. Those Nicrosilminds are given to another Ferring or Misting, along with the Aluminumind created when unkeying them.
6. That Ferring/Misting compounds Nicrosil in a similar way to step 2, creating Nicrosilminds
7. The aluminum ferring, preferably while also completing step 4, utilizes Nicrosil and duralumin feruchemy to create unkeyed versions of the metalminds created in step 6
This method is logistically challenging, requires a lot of Nicrosil to be burnt, and is pretty inefficient. I think that in all these steps there would be a major loss of potency, but this is a definite way to create unkeyed metalminds with metallic arts as we see them in era 2, and without excisors.
We may be able to use soulstamps to create Nicrosil compounders from twinborns as mentioned below.
What do you guys think? Is this possible? Or am I misunderstanding something?
Edit: Changed Duralumin to Aluminum