Do metalminds ever need replacing?

[kroen]

There was no indication in the books that they do. That's a huge advantage for feruchemy over allomancy; You just get the metals you need and, granted they aren't stolen, you never need to worry about buying new ones. Unlike allomancy where you constantly need to buy metals.

[Phantom Monstrosity]

I suppose in theory if people keep filling the metalmind and then dying, eventually the capacity of the metalmind will be filled up with inaccessible feruchemical abilities.

[Voidus]

Well it's more a matter of just having a different cost, feruchemists have to pay with the attribute they store up, if a feruchemist just bought new metalminds and an allomancer just bought some more allomantic vials, then the allomancer has the advantage.
There's also the problem that they can only store a certain amount of an attribute, so you would need more if you ran out of storage space..

[Oathbringer he/him]

It seems from what we know of feruchemy the storage of a metalmind does not degenerate over time, otherwise the Terris Keppers would have to start buying some conspicuously big earrings to store all the information. On the point of them dying I am not completely sure but I would say that once the person dies there abilities in minds would disappear or something to that effect as no one else can access them it might be possible that other people could use the metalmind as if empty even though others have things stored in it as if empty already.

[Krelian]

At the very least, we know that when two Keepers use the same metalmind, it is partitioned so that each only accesses their own attributes. 

 

I've always assumed that metalminds have a capacity, it's just that to fill them totally would be crippling for a long period of time, which most Keepers can't afford. 

 

I don't think Brandon would have let Feruchemy be unchecked like that. Especially because, if that were so, the powers of a being like the Lord Ruler would be absolutely ridiculous. If you can save hours of strength every day for hundreds of years, you could level mountains by compressing that into an instant. It didn't seem like Brandon wanted that kind of power for anyone on Scadrial, outside of Vin during the brief time she was a Splinter, but still corporeal.

[Vortaan he/him]

At the very least, we know that when two Keepers use the same metalmind, it is partitioned so that each only accesses their own attributes. 

 

I've always assumed that metalminds have a capacity, it's just that to fill them totally would be crippling for a long period of time, which most Keepers can't afford. 

 

I don't think Brandon would have let Feruchemy be unchecked like that. Especially because, if that were so, the powers of a being like the Lord Ruler would be absolutely ridiculous. If you can save hours of strength every day for hundreds of years, you could level mountains by compressing that into an instant. It didn't seem like Brandon wanted that kind of power for anyone on Scadrial, outside of Vin during the brief time she was a Splinter, but still corporeal.

 

Unless you count storing enough age to keep yourself looking 25ish in two thin atium armbands a lot of power. Considering he was fighting a thousand years of aging, that is one hell of a Feruchemical charge, even if you deplete it every three days.

[Krelian]

I'm not saying it isn't a LOT. But we know for sure that Marsh has an expiration date, even if it's still thousands of years off or whatever. 

[Voidus]

Marsh's expiration is more due to him having limited atium to use to compound rather than limited storage, he needs to keep ingesting it to compound so he'll run out eventually.

[Krelian]

Ah, this is true. Wasn't thinking about the Allomantic component there.

[Sirscott13 he/him]

I believe an important understanding is that you do not actually store the attribute in a metal mind, rather store the temporal existence of the attribute. What feruchemists do is simply add a catalyst to their metal minds (charge) that allows them to tap into the temporally displaced attribute. So in theory the charge for an attribute is worthless, only accessible to someone who fits the spiritual catalyst. 

 

This is how they can "compound" the rate by which they access the attribute, because the catalyst simply transfers the temporally displaced attribute. This means that the attributes do not wear down the metal mind themselves, and a relatively small amount of metal can hold an increasingly large charge. 

 

Along this theory would mean that one of two things would happen if a feruchemist died before tapping all of their attribute.

 

a) the charge would not affect someone wanting to add their own charge to the metal mind meaning they are completely independent from eachother allowing for multiple charges to be stored without hindrance to the metal mind. simply leaving the catalyst useless and the power lost to time. 

 

the charge in the metalmind works as a blockage to anyone trying to add another charge to it meaning that the metal mind has become feruchemically useless. A misting however could delete the metal from existance without accessing the charge and just causing the catalyst to be lost forever.

 

If you are wondering how I know this it is because brandon sanderson confirmed that you dont actually put the attribute into the metalmind during one of his Qand A but I do not recall which one. 

[Voidus]

I'd be really interested to see the source for that, I can't think of any interview where he confirmed any new mechanics to that extent and he does talk about storing an attribute a fair bit, I'll trawl through the interview db and see if I can find it in there.