Expensive Spell Components

[Backpack]

I was wondering if there was a hard answer to what exactly are "expensive spell components" looking through forum posts I've seen anything from 50gp-anything with a listed value.

CRB on Magic wrote:

Usually you don’t need to worry about components, but when you can’t use a component for some reason or when a material or focus component is expensive, then the components are important.

The above was the only piece of information I could find in the books and I'm leaning towards anything with a listed value, but I have found some weird outliers to that as well. ex.gold, mercury, and iron on spells with no value, to detect thoughts which requires 1 cp.

Note PFS specifically is what matters here and as I don't have a consistent GM I'd really prefer not to have "GM discretion being the only real answer." Too many times I've gone to a con and have a GM say "that's not how I think it works, and I'm left up a creek."

[Bob Bob Bob]

So the section you quote is, well, not entirely correct. You always need to provide the components (unless you have a feat or class ability that says otherwise), it's just that this item exists:

Spell Component Pouch wrote:

A spellcaster with a spell component pouch is assumed to have all the material components and focuses needed for spellcasting, except for components that have a specific cost, divine focuses, and focuses that wouldn't fit in a pouch. Most spell component pouches are waterproof and can be strung onto a belt or bandolier.

So whatever section you're quoting is assuming that the spellcaster has a Spell Component Pouch and therefore can ignore most components (except for those with a specific cost, divine focuses, or which wouldn't fit in the small bag). I always recommend buying at least two.

So in this case, "expensive" means "has a cost". If it's not a specific item (masterwork weapon and potion of bull's strength are two I know of) and doesn't list a cost then it's in your pouch. Yes, this has a lot of oddities. The material component for Polymorph Any Object is "(mercury, gum arabic, and smoke)". So you reach in there and pull out a wisp of smoke... somehow.

[Claxon]

Yeah, spells which have "expensive" components list a specific price in the spell description. Otherwise, the cost is assumed to be negligible and the item is found in your spell component pouch.

[Belafon]

Read just below the line you found, Backpack.

CRB wrote:

Material (M): A material component consists of one or more physical substances or objects that are annihilated by the spell energies in the casting process. Unless a cost is given for a material component, the cost is negligible. Don't bother to keep track of material components with negligible cost. Assume you have all you need as long as you have your spell component pouch.

This applies for PFS. Unless the component has a listed cost (including "at least x") then your spell component pouch has it automatically.

Note that this also applies to focus components.

CRB wrote:

As with material components, the cost for a focus is negligible unless a price is given. Assume that focus components of negligible cost are in your spell component pouch.

More than one PFS player has been tripped up when trying to cast create pit and being asked by the GM "do you have a miniature shovel costing 10 gp on your Inventory Tracking Sheet?"

[Brother Fen]

It's simple. Anything with a listed cost needs to be accounted for. This isn't the PFS forum either. If you want a specific answer from them, it's best to post there.