Animal / Mineral / Vegetable

[ShakaUVM]

Are elementals part of the animal kingdom or the mineral kingdom?

[Claxon]

Neither. They are outsiders.

And how is this even a question? What are you actually trying to ask about? Animal/vegetable/mineral isn't even a thing within the rules of this game as you are presenting them.

[Nefreet]

I am not aware of a "mineral kingdom", although I haven't read every Pathfinder book that has come out.

[Zhayne]

Air, Earth, and Water would be mineral. Fire, however, is an energy state and thus 'none of the above'.

[Rikkan]

The question appears to be in relation to:
Polymorph any object

[Claxon]

With that rather insighful post Rikkan, I think I now have a better understanding of what the OP is trying to ask. To that end, all elementals are creatures so I would put them under the "animal" category, and for class they would still be "outsiders". They certainly don't qualify as mammalian or anything of that nature.

[Nefreet]

Fascinating.

With that understanding, I would say this probably falls into the realm of GM purview. If it were up to me, polymorphing an earth elemental into a porcelain vase, for example, would be easier than doing the same to any other elemental.

Just consult your GM first and see how they read it as functioning.

[ShakaUVM]

Rikkan, correct, this is a PAO question.

Makes a pretty big difference, too, for the duration of the effect.

[Bizbag]

It's a GM call. My opinion (of what would make the game fun) is that they are living embodiments of, well, elements (gasses, liquids, solids, and reactions), so I'd probably go for "mineral". Going for animal, or even both, could be a fair ruling too.