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kelyphitic rim

British  
/ ˌkɛlɪˈfɪtɪk /

noun

  1. geology a mineral shell enclosing another mineral in an igneous rock, formed by reaction of the interned mineral with the surrounding rock

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of kelyphitic rim

C19: from Greek keluphos pod + -itic ; see -ite 1