Definition of pyrophysalite in English:

pyrophysalite

noun

Mineralogy
  • A coarse, nearly opaque variety of topaz, occurring as large yellowish crystals which swell up when heated.

Origin

Early 19th century; earliest use found in Journal of Natural Philosophy, Chemistry and the Arts. From pyro- + Hellenistic Greek ϕυσαλλίς bladder, bubble + -ite, after Swedish pyrophysalit.