Ngongo Hāpaira Oro me te Wāhanga Hanganga

Ko te ngongo hapaira kua orohia he wāhanga mahi-teitei i hangaia mai i te waikura konumohe kotahi-kiriata (Al₂O₃). Mā te tipu tioata matatau me te oro tika maha-wāhanga, ka tukuna he huinga o te māramatanga whatu, te pakari miihini, me te manawanui wera e kore e taea te rite. Ko ngā mata tino maeneene o ngā pakitara o roto me waho ka taea te tuku māramatanga pai me te iti o te poke, ka waiho ngā ngongo hapaira he mea nui ki ngā tono whatu, haurua-ira, tātari, me te ahumahi.