I was wondering if there is a unit of Investiture, like maybe something Khriss uses.
Yes, but I haven't canonized it yet. Good question. I will eventually canonize it, because I think that people will want it, but I probably won't do so 'til [Mistborn] Era 3, because I want the scientific way of talking about the cosmere to mirror how developed the cultures are, but some of the scholars are beyond where everyone else is. It can be measured. There is a unit.
Like, maybe grams of solid Investiture?
It will probably be an in-world unit of measurement. Right now, to talk about it online if you want, the unit is probably gonna be based around Breath, because a Breath is a distinct amount. Whereas in most of the settings, there's not a distinct amount. Like, how much Allomancy, things like that. How much can a gem hold. It really depends on how the gem is cut, and how long the gem has been out. So... the Breath is a really easy one, so it's become the unit. But there will probably be a fantasy term for it. I might just call it Breath. That's why I'm not canonized yet. But if you guys wanna talk about it in Breath terms, that's probably the easiest.