delessite (countable and uncountable, plural delessites)
- (mineralogy) A magnesium-rich form of chamosite that is a member of the chlorite group.
1905, B. K. Emerson, “Plumose diabase and palagonite from the Holyoke trap sheet”, in Bulletin of the Geological Society of America, volume 16, page 105:
- Several delessites and chloropals occurring in basalts have a composition very close to that of the glass.
- “Delessite” in David Barthelmy, Webmineral Mineralogy Database, 1997–.
- delessite mindat.org, Hudson Institute of Mineralogy, accessed 29 August 2016