Working on finishing up the rules, as suggested. (belated thanks for the suggestion )
Alchemy is the science of binding magical energies into mundane substances, allowing anyone to use or benefit from the spell. Alchemist spells are, in essence precast and carried around in the form of expensive potions and powders which must be consumed or thrown to activate the effects. The materials vary in their volatility, but all eventually become inert if not used.
Cost to produce an alchemical item is either explicitly listed for purely alchemical spell, or, for items binding Standard (non-mystery) spells, the circle of the spell. In general, a compound can be of any expendable material, traditionally a potion, but also powders, unguents and oils can be used, as could a candle, a box of powder or a chicken drumbone (if one is so inclined); the point is that the compound must be directly expended by the user, such used destroying the compound. generally, the user must do somthing with the compound involving their body -think medicinal compounds and snakeoil.