Alchemical Schools of Magic

[Drakevarg]

Just another quick thread to answer a question that's bothering me. For some unnecessary contextual details, I've been working on a homebrew for nonmagical potion brewing, as a way to cover some gaps in my low-magic setting (don't want to discuss the wisdom of a low-magic setting, tired of that, thanks). However, in my notes for this project, it seems that in addition to the usual rules for potions (levels 1-3, range touch, casting time one minute or less), there's another conditional:

Conjuration, Necromancy, or Transmutation schools only.

Problem is, I can't actually find any passage in my books that corroborates that. So my question to the forum is, is this actually an official rule in any way, shape or form, or is it something that I concluded throughout my examination of the potion list and then forgot about? It doesn't necessarily sound off, but I can't confirm it in the least.

[Eldest]

I mean, potions of Heroism are a thing, and IIRC that's an enchantment. Protection from Evil is an abjuration. Oil of Daylight is a thing, so not a potion but evocation. So, if I understood the question right, no, that isn't a requirement.

[Zaq]

To add to the list of counterexamples, potions of Invisibility are totally a thing, and that’s Illusion. Potions of Tongues are listed in the DMG/SRD, so there’s your Divination.

[Drakevarg]

Hm. I wonder where I got that requirement then. I'm not especially well-versed in the schools of magic, it's something I largely ignore, so I wouldn't have added it as something I think "should" happen. I suppose it emerged when I removed the potions I felt inappropriate for my setting and looked at the schools of whatever was left. I suppose that's what I get when I have years of heavily abridged notes laying around without any explanation of the logic behind them.

Thanks for the help, this thread can be closed whenever.