The Spellgrinder's Apprentice

The Spellgrinder's Apprentice is also known as Silverboy (US edition).

A spellgrinder's apprentice like Tommo rarely survives long enough to become a spellgrinder. Most of them die of the quivers, or from wounds suffered when their turn-knife slips. Working, sleeping and eating in the cellar with magical stones, their skin acquires an eerie silvery sparkle. It's practically impossible to escape from their underground prison, and if they do, the phosphorescent glow of their skin shines like a beacon for all to see. That's why Tommo is running, running as fast as he can to the coast. He has been granted sanctuary for eight days and must leave the shores by then, or face the hangman's noose.