 1973, unable to identify the constituent phyllosilicates, gave matrix as "poorly characterized phase" (PCP).Cronstedtite was published by Kurat and Kracher in 1975.Tomeoka and Buseck, identifying cronstedtite and tochilinite in 1985, gave matrix material as “FESON” (Fe-Ni-S-O layers), as well as the backronym “partly characterized phase” for “PCP.” Later authors would use the term TCI, tochilinite-cronstedtite intergrowths.