Irionite

Irionite — known in common speech as witchstone — is the green crystalline substance that is the indispensable fuel of high magic on Callidore. It is described as a kind of magical green amber, a stone that can hold and augment arcane power. The word irionite is the Perwynese / scholarly term used by trained magi and the Arcane Orders; witchstone is what footwizards, hedgewitches, peasants, and most mundane folk call it. They are the same substance.

In its raw form a stone holds arcane power like a battery holds charge; bonded to a living caster it multiplies the mage's reserves many times over. Every High Mage in the series — Minalan, Pentandra, Tyndal, Rondal, and the rest — owes their rank to the possession of a bonded shard. With irionite even routine spellwork becomes trivially easy: Minalan notes that peppering an area with waiting glyphs, or casting scrying spells to detect gurvani, is made as easy as trimming his toenails by the sphere on his chest.

Irionite is of the Alka Alon's world; they have known and used it for millennia. Their scholars caution that not every human body and mind can safely bear its continued use — some humans have reacted poorly to prolonged exposure, while others have used it their whole lives with no ill effects. Ithalia and her elders take an active interest in monitoring humani who bond with it, examining Minalan and the pregnant Alya for any harmful effects of prolonged proximity.

A bonded sphere is not a single crystal but can be assembled from various bits of irionite by an Alkan artificer, and gifted with a library of Alka Alon songspells that the human bearer may not even fully understand — magic that depends on their sung, resonant spellwork rather than Imperial techniques. Even the mightiest such sphere carries a warning: using Alka Alon magic through it can be dangerous to a human caster.

The Spellmonger's Seven are the elite class: Alka-crafted irionite spheres distributed to Minalan's most trusted lieutenants. Most other High Magi carry stones derived from shaman-stones captured, cleansed, and re-bonded through the Arcane Orders' licensing process. Gurvani shamans, by contrast, wear their raw irionite shards openly.

The Royal Censorate of Magic enforces the four-hundred-year-old Bans on Magic, under which possession of even the smallest piece of irionite is usually a death sentence, its super-jurisdictional authority leaving no appeal to civil courts. The abolition of the Bans and the subsequent licensing of witchstones through the Arcane Orders is the political and magical revolution at the heart of the series.