Light fire ink, vial

Description

This alchemically infused ink helps to ensure that a secret message is destroyed after being read. If light strikes the ink after it has dried, chemicals cause it to spontaneously combust within 1 minute. The combustion is small—not significant enough to ignite anything but paper. Ink used on other materials such as stone or wood simply vanishes, leaving no trace of the writing. A vial of this ink holds enough to write 10 brief messages of no more than 50 words each.