Saltpetre is another name for the mineral form of potassium nitrate. Filings and rasplings of it are used as an ingredient in Polyjuice Potion. It was kept with other potion ingredients in the Potions Classroom at Hogwarts School of Witchcraft and Wizardry.


Behind the scenes

  • Saltpetre is an ingredient in gunpowder and was known to Chinese alchemists as early as the 9th century CE.[1] It was also historically used in Europe as a food preservative.[2]

Notes and references

  1. Glick, Thomas F.; Livesey, Steven John; and Faith Wallis. Medieval science, technology, and medicine: an encyclopedia. Psychology Press, 2005.