Iceland spar

English Noun ~ A transparent form of calcite, used to demonstrate the polarization of light. en Iceland crystal en 2006 Thomas Pynchon Against the Day 127 Vintage 2007 portions of the original aragonite—which make up the nacreous layers of the pearl—had, through “induced paramorphism,” as it was known to the artful sons of Nippon, been selectively changed here and there to a different form of calcium carbonate—namely, to microscopic crystals of the doubly refracting calcite known as Iceland spar. Translations A transparent variety of calcite Chinese: Mandarin: cmn 冰洲石 Anagrams en aacdeilnprs spiral dance