dichroite

From dichroic +‎ -ite. So called because it presents two different colours when viewed in two different directions.

dichroite (countable and uncountable, plural dichroites)

1. (mineralogy, archaic) Iolite.

• “dichroite”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.

• David Barthelmy (1997–2025), “Dichroite”, in Webmineral Mineralogy Database.
• “dichroite”, in Mindat.org‎^[1], Hudson Institute of Mineralogy, 2000–2025.