264 / | HD | PLASTIC AND NONMETALLIC ARTICLE SHAPING OR TREATING: PROCESSES |
603 | DF | OUTSIDE OF MOLD SINTERING OR VITRIFYING OF SHAPED INORGANIC ARTICLE OR PREFORM {30} |
629 | DF | .~ Producing article having plural hollow channels {1} |
630 | .~.~ Producing honeycomb shape {1} | |
631 | DF | .~.~.~> From cordierite (i.e., 2MgO.2A12O3.5SiO2, iolite) |