Major or Minor. It seems less wide than Fire but at the same time feels wider than Molten metal so I am not sure
If limited to already formed volcanoes, i would say minor because of the geographical limitations.
If also allowing it to add to manipulating potential and/or creating new volcanoes, then maybe that is enough to bring it up to major... Basically, if you expect it to be limited(by player or SG) then minor for sure, otherwise either is possible.
You're still limited in the sense, that creating a volcano, where none was before, is very hard. I'd say it's a rare enough event, to make it a Minor focus IMHO. Like lightning, a lightning spell is lvl 35 and does a heap of damage. Barring the slightly lower level spell of creating a natural lightning (from a storem cloud) rather than from your hands - for the same damage IIRC - you don't get any other lightning. You can't simply make a lower level spell, with a pocket lightning doing little damage. Medieval paradigm doesn't include any other lightning, other than the very destructive ones. Same goes for volcanoes IMHO.
Eeh, i think you misunderstand, i said that it might be a major if it can affect volcanoes in any conceiveable way, INCLUDING creating/manipulating potential volcanoes, because that means you can tap into an enourmus amount of power and do so almost anywhere.
Ie, it becomes a problematic matter of definitions, and if you use a more limited definition making it a minor is just fine, but the less strictly you make limits on what exactly constitutes a volcano, the more likely you should make it major focus.
For example, if you´re in a spot with an volcano that has been inactive for millions of years, does it still count?
Or if you try to make use of a the geological formation that WILL BE a volcano in perhaps a thousand years, does it still count?
those arent in the present volcano...
Very, very minor IMHO.
Most of these spells will be rituals too, since a big and powerful volcano is, well, big and powerful, with correspondingly large magnitudes, yet a small or wimpy volcano is extremely unnatural, with a "you can get the super size for only 59 cents more" spell level.
I think that should be Major, because a genius locii of volcano, in RoP: Magic, have one Focus Power in one volcanic aspect, the Lava. That means that the differents and severals aspects of the volcano are really greats for a minor.