DracoAdamantus

I'm confused on this one. Yes obviously if you trapped him at the bottom of the ocean by chaining him to a rock or something he's eventually going to run out of healing and die, but how would the his gold spikes prevent him from swimming?

Oh I wasn't saying the nicrosil was being tapped, I agree with the idea of them working through a form of bonding. What I was pointing out is that Sanderson said that it works like a Coppermind in the sense that abilities stored in medallions don't work like most attributes in which it is a span of time, it is a discrete thing you can access. This is what I was getting at with the theory of the bands having an investiture power source of some sort. Sanderson said that the powers are not drained over time, they are discrete abilities that are "taken" (either tapped or bonded, whichever it is), then returned to the medallion when done. So what exactly did wax feel draining away as he was using the bands? Maybe it was pure investiture from Preservation (manifesting around him as the mists) that fuel the bond.

I don't want to take this thread too off the rails of the Atium discussion, but rereading this as I've been finishing my reread of Era 2 is turning some gears in my head. Oh yeah, I have a whole long theory on medallion mechanics that works off of the premise that they are forming a bond of some sort: But to the point of the relevant WoB in question, I'm not inclined to agree that vanilla nicrosil feruchemy is temporary tapping, at least not all of it is. Honestly just seeing a regular nicrosil feruchemist use their powers would provide a lot of answers. If you can store different kinds of investiture, just like how different senses or different kinds of connection can be stored, I think that whether it is a temporary or permanent effect from tapping depends on what type was stored. If it was innate investiture, ie. the investiture that gives you an ability in the first place, then it would be a permanent effect, giving you the innate ability permanently. If it was kinetic investiture, like the investiture accessed when using allomancy, then it would be temporary, powering the effects you use it for. Which leads me to this thought: Can you store investiture that is actively performing an effect? And when it's later tapped, gain access to that effect not because you have that actual power, but because you are accessing investiture that was keyed by that power? Allomancy works by gaining kinetic investiture from Preservation. It is possible for this investiture to be sent/stored somewhere, as we see with the primer cubes taking in allomantic investiture, and the later allomantic grenade designs being able to be primed by an allomancer several hours beforehand. Feruchemy works by converting your own attributes to static investiture, to be accessed later as kinetic investiture. Can these types of investiture be stored in a nicrosil metalmind? Allomancy would be easy, a twinborn with nicrosil feruchemy could just burn metals and store the investiture directly into a nicrosilmind for future use. Feruchemy would require some having of the system, but still possible. To store something like strength in nicrosil, you'd first have to store it in pewter (to convert the strength into investiture), then tap the pewter while simultaneously storing it into the nicrosil. But if that works, then that opens a whole host of possibilities with compounding and nicrosil feruchemy. A nicrosil feruchemist could theoretically tap any kind of allomantic effect or feruchemical attribute. This wouldn't grant them the ability, they wouldn't be able to burn metals or store attributes, but they could access the premade reserves of investiture. This went a bit beyond the original point of this response, I just had the thought as I was typing. Was it ever truly established that their nicrosil portion ran out? If this is talking about the scene in TLM, I know they said they were "drained" but was it specified if the feruchemical reserves were all drained, or if there were no abilities within it? In any case, how that went down with the Malwish is super sketchy, and I highly doubt was as simple as "someone drained the bands". In any case, I'm actually very confused now by how the bands and the medallions actually operate. There's the WoB that when you tap the nicrosil portion of a medallion, it does not run out over time, it functions like a coppermind. But it is also mentioned by Suit in BoM that they don't know how to recharge the heating medallions. At first I thought this implied the Set hadn't cracked identity blanking yet, but in the first few chapters of TLM it's mentioned that the Malwish have withheld a lot of information on the medallions from the Basin, including how to recharge them. I don't think it's specified then either if that means "refill with attributes", or "recharge with feruchemical ability". In any case, there is something more complicated to making the medallions work. An idea I've had floating around is that that the Bands, and possibly all unsealed metalminds in general, are powered in part by the Mists. When Wax and Marasi were using the Bands, they noticed there being mists around them, and they feel like the mists are originating from them. The mists, as we know, are a manifestation of Preservation's power. What if the bond that an unsealed metalmind forms has to be sustained by an active power source, such as the mists? This would make the WoB and the recharging issues work at the same time. There is a storage of innate investiture in the form of the actual ability given, and a storage of Preservation's investiture that is used to power the bond that gives you access to the ability. When a medallion is drained, it hasn't used up the power stored inside, it no longer has the juice to give you access to the ability. It would just feel like mundane metal until the "battery" is recharged with unkeyed Preservation. I just realized something...we've only ever seen youth compounding with the retconned atium-electrum alloy that the pits produced. But Wax's method assumedly created pure atium. That might do something more special/more permanent. My first thought is that it would be a more efficient de-aging, playing much stronger into the "spiritual identity" aspect of it. The most common theory I see about pure atium is that is that using it allomantically would let you see into the spiritual realm and give far visions of time. What if instead of storing youth, pure atium did something like store your body's or spirit's "state"/"status"? I'm not quite sure how to explain this idea as an encompassing attribute, but looking just at aging, it would be a storage of "being that age" rather than "being this much younger". Using regular atium, if you have 8 hours of "50 years of youth" saved up, a 100 year old man could use that to become 50 for 8 hours (50 years younger, 1-to-1 de-aging). A 200 year old man could only be 50 for 4 hours (100 years younger, 2-to-1 de-aging). Using pure atium, you would instead create a reserve of "being 50 years old". An 8 hour storage reserve of that would give anyone that taps it 8 hours of being 50, no matter how old they actually are. Does that make any sense? I have a feeling this is a convoluted theory, since the question therein is what exactly happens to you when you are storing "status"? Storing 50 years of youth makes you 50 years older while storing it, but what the heck is the opposite of "being 50 years old"?

These are ones that really mess with my head to think about, because it's still done over a period of time, but is still a distinct resource because your body is constantly using it. Memories are quick, you have a memory, you store it, and it's in the metalmind. And your body doesn't constantly have to replenish that particular memory. But take breath for example. It's stated that a gasper ferring will feel out of breath while storing, and not have to breathe while tapping. There are two interpretations to what that means: They are storing based on the oxygen itself. Half of the oxygen they breathe in is going into the metalminds. When they tap breath, they gain oxygen from the metalminds instead of from the air, and will not to breathe at all until the stored breath has been used up. (I know that the chemical process of breathing is more complex than just getting oxygen, and getting rid of carbon dioxide is also essential to the process, it's just simplified for this explanation) They are storing based on their ability to hold their breath, or perhaps their efficiency at using oxygen. Let's say normally you are capable of holding your breath for 1 minute. If you were storing half of your breath, you'd only be able to hold it for 30 seconds at a time if you tried. If you did that for an hour, you could tap it and have an hour of being able to hold your breath for 2 minutes at a time, or half an hour of 4 minutes at a time, or 15 minutes of 8 minutes at a time, etc. I'm inclined to assume it's the first way, but from what we know of feruchemy at the moment there isn't a clear conclusion to draw for which it actually is. I think that investiture has to work the same way as well, because of how the unsealed metalminds work. The issue I see here is that the requirement of youth goes up exponentially the older that Marsh gets. It gets harder and harder to sustain as time goes on. For simplicity of numbers, let's say Marsh was 50 when he was spiked, keeps himself at age 50 using feruchemy, it has been 400 years since the Catacendre, and speeding up feruchemical tapping is perfectly efficient. If a Sliverist spends 8 hours aged 50 years, then Marsh can use that to de-age himself 50 years for 8 hours, or 100 years for 4 hours, or 200 years for 2 hours, or 400 years for...1 hour. Without compounding any youth that is given to Marsh effectively decreases by a factor of 8. He'd need one person to store 50 years of youth for 8 days straight just to keep him alive for 1 more day. So two dozen priests storing 8 hours a day = 24 x 8 = 8 days of 50 years stored = 1 day of 400 years stored. It's doable, but an incredible risk and hassle to have to change out the metalminds every single day. Let's instead say Sliverist priests really devote themselves to the cause and keep the metalminds running 24/7. You'd only need 8 priests to keep Marsh alive, assuming no missed appointments. It would be still be a huge hassle, and still need to be changed out every day. But going with your example of a dozen or two dozen devoted priests who store youth perpetually, that's 24 days of 50 years stored = 3 days of life for marsh stored for every 1 day the priests spend storing. Now we're talking. Marsh could even use the excess to store up in his spike over time, giving him a "battery" in case something goes wrong. Though I hate to say it, but if there's a way to continue to create more atium as Sazed implies at the end of TLM, then I still think continuing to compound is the way to go. Though maybe using youth from parishioners would help cut down on the amount of atium lost per compound, if it's still extremely hard to create.

Ah that's right. I had been recently thinking about copperminds and that being fresh in my mind made me think that youth was something distinctly stored and retrieved, rather than a time span thing. Which led me to think the solution was simpler than it actually is. Compounding would have to be used in that case, unless there are hundreds of parishioners constantly storing youth for him, since Marsh is over 300 years old and the amount of Feruchemical youth needed to stay alive goes up exponentially to keep you at the same age for long spans of time. And there's a resource issue on making that many metalminds due to Atium's scarcity. Maybe instead, what if priests of Sliverism had a medallion as part of their vestments, and as part of their devotion they were constantly storing youth (& identity to make it unkeyed).

It would need to be a special unsealed metalmind for this purpose, because it's unclear if attributes stored via an unsealed metalmind by your average user are tappable by others. We never see actually a medallion be filled and then tapped by a different person on screen. We only ever see the weight medallions be filled, and the heating and connection medallions tapped. Suit remarks in BoM that they "haven't figured out how to refill them [the heating medallions] yet", which wouldn't be the case if anyone could fill it. Plus the Malwish have dedicated people whose whole purpose in life is filling heating medallions, the Firemothers and Firefathers. This implies there is more to filling an unsealed metalmind for general use. I think that even with an unsealed metalmind, any stored attributes are still keyed to your identity. At minimum you'd have to be blanking identity for the stored attributed to be accessible to another, either by regular Feruchemy or by compounding. Now, if there was an unsealed metalmind that gave someone both Atium and Aluminum Feruchemy, now we're talking. I absolutely see some sort of eucharist-like ritual in which the priest is presents a holy relic for parishioners to touch and give some of their life to as a gift to Death. Even if it's a single parish of say 100 people, each giving one day of life over to Death at the weekly service, that's an extra year's worth of life for Marsh every 3 weeks. And that's without any compounding at all. For the average parishioner, the decrease in lifespan wouldn't be super noticeable. Each calendar year you would age just 50 extra days. For your lifespan to decrease by 5 years, it would take approximately 35 years of doing this weekly ritual.

Hmmm...that's a very good question. I believe that both storing and tapping metalminds are considered kinetic investiture, because of the fact that Ruin was able to alter memories stored in a coppermind. I can't find the exact information, but I remember hearing somewhere that the memories are safe in your own mind, and safe in the coppermind, but during the time of storing/tapping they are vulnerable to Ruin's alterations. As for why it isn't sensed, I did find this on Arcanum: It is implied that with training or savantism, Allomantic bronze can sense other sources of investiture. Allomancy is just very easy to sense because it's pulling in a decent amount of investiture directly from the spiritual realm. Feruchemy, on the other hand, is a comparatively small amount of investiture, and doesn't cross realms when it is being accessed. That plus sensing Allomancy is using Preservation's power to detect more of Preservation's power, it may be easier in that regard because it feels more familiar? Regarding Vin not seeing pulses from Sazed, did she ever in the series specifically try to observe him storing, or did that just never come up? The same question goes for tapping metalminds, is there any direct reference to someone trying to sense it in the books? I do have doubts on if storing would even have readable pulses, because it's technically energy becoming investiture within the metalmind, the investiture isn't actually doing work until it is tapped later. But at least when tapping, it does give off pulses, just once so weak most can't sense them.

I meant that it's a point of contention in the discussions I've seen, not for me personally. I did go on in the next few sentences to touch on the fact that metals and gemstones are both crystals, which I doubt is a coincidence. I don't think it's beyond reason for half of Hemalurgy to be tied significantly to the other metallic arts, as the interplay between Preservation and Ruin would likely cause their magic systems to become intertwined. Preservation and Ruin had to work together to create Scadrial, and to create their own humans. Plus, shards don't really have a direct hand in the creation of their magic systems, and the main thing the intent of the shard influences is how that system is accessed (https://coppermind.net/wiki/Initiation). Since Allomancy and Feruchemy are inborn abilities from spiritual genetics, it makes sense to me that a significant portion of Ruin's invested art would be tied to the people he helped create (as only Scadrians can be naturally born with Allomancy or Feruchemy). That being said, I also don't think those 8 metals are limited to just stealing Allomancy and Feruchemy, it's just much less intuitive. The catch being that each of those 8 metal can only steal a certain type of power based on its spiritual makeup, and we haven't seen any invested arts that would form that match yet. Sanderson has always stated that there is something special about metal in general in the Cosmere. In Rosharan fabrial tech, metal is used extensively in directing and modifying the attributes of the spren trapped within a gemstone, with different metals having different effects. Different metals are also used in sprouting to regulate aether spore behaviors. From what we have seen, I think that each metal has a unique way it can shape and influence investiture, regardless of the investiture's form or source. However, just like in Feruchemy, only certain forms of investiture can be stored in certain metals. I think that any abilities that come from a permanent aspect of the spiritweb, rather than an external source through a bond, could be spiked out using one of the basic metals that removes Allomantic or Feruchemical abilities, instead of having to resort to Nicrosil, Lerasium, or Atium. Which metal it corresponds to depends on the "template" of that ability in the spiritweb. As an example, maybe the reason only physical Allomantic powers are only stolen by steel is that all the physical Allomantic powers have a similar "template", a template that the specific crystalline structure of steel is able to hold. If you steel spiked someone with a different invested ability that had a similar template to physical Allomancy, you would be able to steal that ability. Unfortunately, we've never seen someone try to spike out a non-Scadrian ability from someone on-screen. Going back to the crystal spikes themselves, I was wrong in calling them a "hack" of the system. Thinking about it more, I would posit that they are utilizing hemalurgy, but not in the traditional sense of giving a stolen attribute. I view Hemalurgy as having three distinct applications: Investing an uninvested spike by stealing attributes from another Using invested spikes to attach stored attributes to another's spiritweb Using invested spikes to modify a spiritweb in a way that it alters biology (Kandra, Koloss, and Chimeras) Thinking on the nature of metal, and how it is used in fabrials: We established that specific metals store specific kinds of investiture, due to its spiritual blueprint. Specific gemstones hold specific types of spren, and there is no indication that metal can store spren/stormlight, or that gems (infused or not) can be used to alter a spren-gem's output. So even though it's clear that there are similarities between gemstones and metal throughout the Cosmere in their ability to store investiture, they aren't interchangable. My personal theory is that applications 2 and 3 of Hemalurgy can theoretically be used with any invested spike, regardless of the investiture inside or the spike's material (though obviously it must be a material that can hold that investiture). However, I also think that metal's property to shape and influence investiture is essential to the theft of attributes with hemalurgy. TL;DR - Any already invested spike of crystalline material can be used to Hemalurgically modify a spiritweb, but only metal spikes are capable of Hemalurgically stealing from a spiritweb. Aside from aluminum, at least. Ralkalest (the unforgeable metal) is the name for aluminum in the Rose Empire, and Surgebinding does not work on aluminum. But aluminum is also the special case for pretty much all sources of investiture (I also have much longer observations on that I'm trying to compile).

A few WoBs seem to indicate something like that may be possible.

I don't see how it being a growth of investiture on the spiritweb would be countered by the fact that savantism can't be transferred hemalurgically. The theory feels pretty sound even with that fact. I imagine the scenario like this: There's a specific point in the spiritweb in which that allomantic ability is stored. That part is made to withstand the flow of investiture from using allomancy. However, the rest of your spiritweb isn't, and extended channeling of investiture through your spiritweb will cause lots of stress on it, causing it to develop micro-fractures that the investiture builds up in (I imagine it to be like plaque building up in an artery over time). In this case, the savantism isn't "stored" in the place of your spiritweb where the allomantic ability is, it is in fact almost everywhere BUT there. So when you spike out the allomancy from someone, you are removing the one portion of their spiritweb that isn't affected by the savantism. In this case, I suppose if you were to spike an allomancer for a non-allomantic attribute (like physical strength or senses, for example), it would take some of the contaminated spiritweb with it. But I think that contaminated part would be small enough compared to your own spiritweb that it wouldn't really be noticeable (since the savantism would be the result of almost the entirety of someone's spiritweb being contaminated in this way).

I've heard significant debate for both sides of the argument of if the spikes are technically hemalurgy or not. Even though hemalurgy can work on any world if you know of it and have the correct intent, the main point of contention is the fact it's still a metallic art, and Moash's spikes are crystal, not metal. I am of the opinion that they function on a hemalurgical premise, but are another "hack" of a magic system. Metals and gemstones have both been observed to be capable of storing investiture, and both have a crystalline structure to their atomic makeup (I have thoughts on how investiture storage works due to this, but that's for another post). I think that they operate off of the hemalurgical premise of artificially attaching things to your spiritweb, but not using stolen attributes. I heard a theory some time ago that the spikes contained void spren. That being said, even before the spikes that man almost certainly had a damaged spiritweb, and moreso now with the spikes. I think that he is more vulnerable to any myriad of invested beings. Most likely the Unmade. I don't think connection to Ruin, or at least actively having a spike in you is strictly necessary, once there are cracks/holes in the spiritweb that path is open for things to slip in. Paraphrasing from a comment on Reddit: In Secret History, Kelsier can send an entire vision at Spook (who had been spiked for a time but no longer had it at that moment), as long as Ruin isn't blocking the pathway. He can also communicate with someone mad by shouting at them in Cognitive Realm. Having a spike certainly makes it easier though, and we see Bleeder communicate with Wax in Shadows of Self in the same way. So these two things together tell us: A spike isn't necessary for a person to be whispered to through the cognitive/spiritual realm, they just need a damaged spiritweb. Beings other than Ruin that can whisper thoughts into a damaged person's head.

This probably gets into the weird metaphysics of the Spiritual Realm, but how does that work? Space and time may not matter in the Spiritual Realm, but it certainly does matter in the Physical Realm, because you can only sense metal objects within a certain radius of yourself To clarify, when I was referring to a bubble, I meant the means in which the investiture propagates. If I could see the connections to the metal form in slow motion, in either realm, would that appear as a series of separate individual lines shooting out and connecting me to sources of metal, or would it appear like a shockwave propagating out from my center? Ohh okay, so is this to say it's a similar effect to a copper cloud in that where it interferes with an area behind it but not as strongly as the area within it? To play out a different scenario, let's say I had an aluminum box sealed on all sides, and three identical pieces of metal: One inside the box (surrounded by aluminum), one behind it (aluminum in the path), and one off to the side (no aluminum in the path). We also say the aluminum is not thick enough to completely block my allomantic push on the piece inside the box. When I burn steel, the strength of my push would be weakest against the piece inside the box, strongest on the piece off to the side, and the one behind the box would be somewhere in the middle. Is that about right?

The covering everything with humor is the crux of the annoyance. Even when she is being serious, she is still behaving like it is a joke. Even when she cares, she doesn't act like she does. It's that inability to turn off the comedy when it's inappropriate that I can't stand. I've known people like that, and they are some of the most insufferable people to be around.

Okay, I think that ultimately answers my question. Since it may be possible for the bolt to be affected when the direct line between allomancer and bolt is blocked with a thickness of aluminum that will fully block their allomancy when the bolt is surrounded by the same thickness, then that means that the actual investiture directed by allomantic steel and iron is not a straight line like the metal lines themselves, but also in a bubble/cloud (like most of the other external metals) that can "leak" around the aluminum to connect you to sources of metal (just not as efficiently). Am I understanding that right? That's more or less what I was trying to find an answer to. Another way I thought of to word it would be: "Can area of effect investiture curve/leak around an aluminum shield that isn't 100% sealed?" Or to make it even more specific: "If you were able to actually see the investiture itself moving to form the metal lines when iron/steel is burned, would it look more like a bunch of individual lines shooting out from you to sources of metal (not the metal lines, I mean how power moves to find the metal to form those metal lines), or would it look like a bubble or a cloud of influence propagating from your center?"

Right, which is why I clarified with a specific scenario. My question was about how does it differ between something completely shielded by aluminum, and aluminum that is just "in the way" of the direct path. Ultimately, I am trying to figure out what the restrictive properties of aluminum are for investiture, for a concept I have for potential fabrials and malwish technology. To explain the scenario a different way, I put a bolt in an aluminum box, then burn steel, and get no metal lines to the bolt in the box. This tells me the aluminum has completely shielded this bolt from being steel pushed. The thickness of the metal and size of the bolt don't matter here, because I have a baseline control confirming that this is enough aluminum to block this particular bolt when completely enclosed. I then take the bolt out of the box, and set up a piece of aluminum the same thickness as one of the box's walls between me and the bolt. I burn steel again. One of three things can happen: No metal lines form. The metal line forms, but my ability to push the bolt is weaker. The metal line forms, and I can push on the bolt with my normal strength.

My question is more about the way the aluminum is blocking in terms of the position of the objects, rather than the thickness. Let's say there's a sealed aluminum box with a bolt inside it, and I find that the aluminum interferes enough that I cannot form metal lines to the bolt. If I instead set the bolt on the table, and put just one of the walls of the box between me and it, so that the aluminum was in the way of the direct line between my center of mass and the bolt's center of mass, would I be able to form a metal line to the bolt or not? What if we're positioned in a way that I can actually see the bolt, either through mirrors or angles, but that line from center to center is still blocked?

I know that aluminum itself is allomantically inert, and will not be detected by burning iron or steel. But if there was a bolt sitting on the table, and then a vertical aluminum sheet was slid in the way so that it blocked the straight line between my center of mass and the bolt, would I be able to detect and push on the bolt? I know this wouldn't work if the bolt was encased in an aluminum box, but what about when aluminum just blocks the path of the metal line? As an extension of this, how exactly do aluminum hats block emotional allomancy? Emotional allomancy isn't sent out in distinct lines like steel and iron, it's more of a wave/cloud. Since the head isn't completely encased in aluminum, one would think that some would still make it through. My first thought is that it doesn't make you completely immune, but it blocks enough from the average soother/rioter (like 95%) that they're basically ineffective. But if there was a sufficiently strong allomancer (either through savantism, spiking, or just stronger powers), they could riot/soothe hard enough that that little 5% that makes it through the unshielded portion is enough to affect someone.

I thought when he said it was emotional Allomancy, at least when he said that to Marasi at the end of AoL, he was talking about using it on her to make her follow him into the alley. The conversation was something like (paraphrasing): "Sorry to have brought you here this way." "What way?" "Emotional Allomancy." Regardless, I'm of the opinion that what Marsh is actually doing is Feruchemically storing either identity or connection between individuals (or both), which makes him seem nondescript, unimportant, and ignorable to people. Just like any other random person you pass on the street. People do see him, but their brain ignores him. Like how your nose is always in your peripheral view but you don't notice it unless you look for it. Or like the perception filter keys in Dr. Who. Then, when the metalminds fill up, he taps them all at once. This release of identity and/or connection is so powerful that it has helped build the mythos of Ironeyes on Scadrial, connecting the identity of Ironeyes to people's perceptions of Death. Doing this over and over for hundreds of years could be strong enough that it causes even other worlds to shape their perception and mythos of Death to the identity of Ironeyes.

I think we aren't looking at the actual power that is Hemalurgy correctly. Allomancy - Burning metals to access Preservation's investiture Feruchemy - Storing your own attributes in metal and retrieving them later Hemalurgy - Stealing and transferring parts of a person's spiritweb using metal spikes The only actual power of Ruin at play here is everything about the spikes EXCEPT for whatever was stolen. The facts that spikes can steal attributes and abilities, that spikes can attach parts of a stolen spirit web to another, and that stabbing someone through the eye or heart with a hemalurgic spike doesn't kill them, that's the power of Ruin at play here. But I would think the stolen piece of the spiritweb itself is the same as it was before it was stolen (aside from being decreased in power due to the net-loss), it doesn't automatically become "of Ruin" when it is stolen. Compounding with spikes, even if you can get over that compounding with hemalurgy issue, would only store up a bunch of investiture from Preservation.

This is more or less what I was getting at, I think. The investiture doesn't have enough identity to actually think and make decisions, it's not consciously choosing to form a bond. It's more like a program. When a person has the correct intent, they "slot in" to those open connections, the investiture detects being part of a system where it is connected to (what it believes to be) a Scadrian feruchemist, allowing the person the connected person to direct the power.

I'm still of the belief that Feruchemical aluminum is storing identity. Whether it can be actually tapped or not remains to be seen, but in the Ars Arcanum it still specifies that aluminum stores identity, instead of something like "drains" or "lessens". And when the mechanical functions of metals within a metallic art operate differently, it is generally specified. On the Hemalurgy table, there is a distinction that aluminum removes all powers, but other metals steal powers/attributes. So I'm inclined to believe that the identity is in face being stored in the aluminum. Which, if that is the case is extremely frustrating. In the real world scientific community, this is an called falsifiability. That is, a theory can be proven wrong with just one example to the contrary. In this case the theory that "aluminum cannot be affected by investiture or be part of investiture effects" would be disproven by "aluminum works as a metalmind for identity". Which would mean that a more specific explanation is needed. Even just Allomantic aluminum may be an example of falsifiability, because even though its effect is negating other investiture, it is still being used as a part of an invested art. Just swallowing aluminum won't cause your metal reserves to disappear, you have to actually burn it. Allomantically burning any metal is an effect of utilizing innate investiture. So there are investiture-aluminum effects. As for what the actual properties of aluminum are relative to investiture? The general accepted take I've seen is that aluminum blocks/resists investiture. Some properties we see aluminum have include: Hide the contents of a lined space from the sight of shards Protects against emotional allomancy Does not have an atium shadow Is described in @alder24's posted WoB as "inert" Allomantic aluminum will "negate and suck out" investiture when burned (Spoilers for examples outside of Mistborn) My first thought was that aluminum prevents investiture moving into/out of the spiritual realm, but then there's this WoB: Given all this, my best guess on what aluminum actually does is that is an insulator for kinetic investiture (i.e. investiture that is being actively used or expressed), preventing invested arts from passing through or even affecting the metal. Metalminds are an example of static investiture. The attributes being stored within a metalmind doesn't actually affect the metal, it's just stored inside its structure. If this is true, then aluminum metalminds wouldn't break the other rules of aluminum-investiture interactions. Regarding the spiking of aluminum, because aluminum has that strange interaction with investiture anyway, what if the removal of abilities is done by spiking someone outright? Not by killing them I mean, what if hammering a regular aluminum spike with hemalurgic intent into someone, and leaving it in as you would with an invested spike, effectively puts a plug on their powers? When you normally spike someone, you're stapling on a part of someone else's spiritweb to theirs. What would happen if instead you introduced something to their spiritweb that prevents the flow of investiture? It may prevent all of their powers from functioning. The powers are still there, but they can no longer be used because of the aluminum stopping you from channeling any kind of kinetic investiture? If the bind point was in a normally fatal location (like the heart or spine), then their choice would be either permanent loss of powers, or death. Maybe the aluminum actually steals powers, maybe it shears them from the spirit web, or maybe it just suppresses them, but the resulting spike would be effectively the same. Whether that spike has some stolen power inside it or not, there's no way to check for it because of its blocking properties, and spiking yourself with it would just cause you to lose your own abilities. We likely won't have a clear answer or know how exactly it works until Mistborn Era 3, as however the excisors work and how the unsealed metalminds are created will likely explain a lot about identity manipulation, and by extension Feruchemical aluminum.

In either case, the fact that it's magic has to account for some of the scientific inconsistencies, whether it's creating magnetic fields that only affect single objects, or selectively manipulating gravity.

Was looking on the Arcanum for something else, but happened on this WoB: So it is almost certainly identity contamination that prevents you from recalling breath from an object that another placed there.

Was looking on the Arcanum for information regarding identity for something else, and I found this WoB: So this WoB addresses the question pretty directly. Looks like the answer is it's incredibly difficult, and requires more work than just altering your identity and healing to match the new one.

You're the first person I've seen that made a similar connection to my medallions theory, that they work through a sort of bond similar to Spren! You seem to have a similar approach to investiture and invested arts as I do, if you're open to it could I get your thoughts on my theory for the mechanics of using an unsealed metalmind?