Brimstone

Brimstone (BR) is a reagent that is used in the sorcerous arts on Pagan.

Pagan
Brimstone is unprocessed sulfur (differing from the ashen residue used in Britannian magic). The potential flammability of this mineral allows it to serve as a representation of raw power in Sorcery, and it is frequently used to imbue spells with magical potency. Due to the volcanic nature of Mount Morgaelin, brimstone is relatively easy to acquire, particularly near Daemon's Crag.

Adding brimstone to a Sorcery spell which does not require it will result in a conflagration, destroying the arrangement of candles needed for the spellwork and potentially injuring the caster.

Trivia

 * The description of the reagent in The Chronicle of Pagan is a bit misleading, since sulfur (and thus brimstone) is not a stone at all but something entirely of its own. Since the word "brimstone" comes from ancient times, meaning "burning stone" the misunderstanding mirrors the same misleading ideas about the nature of sulfur on Earth.