Invoke the necessary metal components of the geometer
Creo Terram
Range : Touch
Durée : Sun
Cible : Ind
You invoke minerals and purified metals in powder (precious and non precious) :
gold, mercury, lead, silver, iron, copper and tin, inside little stone bowl.
The pure minerals invoke are quartz, salt, suffer, salpeter and coal, inside little stone bowl.
Things needs a geometer for ceremonial casting.
Base 15 +1 touch +2 sun
Level 30
$Invoke the necessary components of the geometer
Creo aquam (herbam)
Range : Touch
Durée : Sun
Cible : Ind
You invoke pure water and oil inside wood bowls and incense.
Things needs a geometer for ceremonial casting.
Base 2 +1 touch +2 sun +1 herbam
Level 10
If your SG insists on this, your magus can of course just cast several spells: no need to change plans or designs.
Also remember, that you need just one more component per spell magnitude above 6. So purified water, oil, candles, flour and incense - or some other fitting ideas - last you up to huge Hermetic Geometry spells, without having to use big CrTe 30 spells at all.
The CrAq(He) spell does not need a magnitude increase for the He requisite because of the level 2 CrAq guideline on ArM5 p.121 box: so it is level 5. And CrHe to create a processed plant product is also easy on your lab time: level 5 too.
You should agree with your SG how many different small Creo spells (or rotes?) you need: one for oil, one for water, one for turpentine, one for gallus ink, one for incense, ...?
You're right small rotes are more easier. With a creo terram base 2 i can create pure salt. Very easy...
I think if you want to create many produit in one spell we need to adjust the target to Group.
With 4 little rotes I can incant level 50 Geometer spells.
Note that using magic to make magic easier is very much part of Ars Magica - at the least, you can get Lab bonuses via repeatedly casting non-ritual spells every day. (Covenants, pg. 122).
As such, there probably wouldn't be any in-game restriction on using magically-created props for the ceremonial bonus; if you need a justification to restrict it however, I'd say that the creation process would require a pretty darned high Finesse roll to replicate the work of a skilled craftsman. HoH:S pg 61 puts that work at a 12; pg. 59 doesn't say how long such a prop would take to make, but I'd put it at a month - so that would be a +3, for a 15 total. That sounds like a reasonable barrier to entry, personally; assuming you've got a house rule to avoid Monte Carlo-ing a success.
Yeah, and you can probably just /5 spont those sorts of effects - even easier if you do D:Conc, and use a /5 sponted Maintain the Demanding Spell to keep it around.