melanophlogite
/ˌmɛlənə(ʊ)ˈflɒɡʌɪt/Mineralogy
noun
A form of silica with a clathrate structure containing organic impurities, which crystallizes in the tetragonal system and occurs as minute cubic crystals or thin crusts on sulphur.
- It was formerly thought to be a polymorph of quartz..
Origin
Late 19th century; earliest use found in Nature: a weekly journal of science. From German Melanophlogit from melano- + ancient Greek ϕλογ-, ϕλόξ flame + -it, after the black colour of the mineral when heated.