dragonglass

Dragonglass is a term used for a naturally occurring volcanic glass that, in geology, corresponds to obsidian. In fantasy fiction, dragonglass is presented as the same material with particular significance, most notably in the world of George R. R. Martin’s A Song of Ice and Fire and its television adaptation. It forms when silica-rich lava erupts and cools rapidly, preventing crystal formation and producing a glassy rock. Obsidian is typically dark in color—black to dark green or brown—and has a conchoidal fracture. It is relatively hard on the Mohs scale (about 5–6) but is brittle, meaning it can break into very sharp edges.

Occurrence and use of real obsidian are widespread in volcanic regions around the world. Archaeological cultures have long exploited obsidian for toolmaking and cutting implements because it can be flaked to produce extremely sharp blades. Obsidian artifacts have been found in many ancient sites across the Americas, Asia, and Europe.

In fictional contexts, dragonglass is prized for its apparent ability to harm certain supernatural beings. In the narrative, weapons and projectiles fashioned from dragonglass are depicted as effective against undead creatures, such as White Walkers. Locations within the fiction universe, including sources on dragonstone, are cited as places where dragonglass can be obtained. The material’s rarity and perceived powers contribute to its prominence within the story’s plots.