Ko te kōhatu puia (e mōhiotia whānuitia ana ko te pumice, ko te basalt porous rānei) he rauemi whai hua, he rauemi taiao hoki, he kōhatu porous tino utu nui i hangaia e te karāhe puia, ngā kohuke, me ngā mirumiru i muri i te pahūtanga o te puia. Kei roto i te kōhatu puia he maha ngā kohuke me ngā huānga iti pēnei i te konutai, te konupūmā, te konumohe, te silicon, te konupūmā, te titanium, te manganese, te rino, te nickel, te cobalt, me te molybdenum. Kāore e pā ki te hihi, ā, he ngaru aukume infrared tawhiti. Whai muri i te pahūtanga o te puia, i muri i ngā tekau mano tau, kei te piki haere te kitea e te tangata tōna uara. Kua whānui ake ōna mara tono ki ngā mara pēnei i te hoahoanga, te tiaki wai, te huri, ngā rauemi tātari, te waro tunutunu, te whakapaipai whenua, te whakatipu kore oneone, me ngā hua whakapaipai, ā, he mahi nui tana i roto i ngā momo ahumahi.

Ko te pātarati he momo toka puia taketake, he momo toka kiato, he toka hanganga pahuka rānei i hangaia e te magma mai i te puia i muri i te whakamatao i runga i te mata. Nō te toka pātarati. He maha ngā wā ka kitea i roto i tōna hanganga toka he hanganga stomatal, he āhua aramona, he āhua porphyritic, i ētahi wā he tioata kohuke nui. Ko te nuinga o te wā, he pango me te hina te tae o te pātarati kāore i te āhuarangi, ā, he parauri pango, he papura pouri, he kakariki hina hoki.

Nā te nui o te pūngao me te pakeke o te papara (pumice), ka taea te whakaranu ki te raima hei whakaiti i tōna taumaha, engari he kaha tonu, ā, he āhuatanga anō hoki pērā i te ārai oro me te ārai wera. He pai te rauemi huri mō te raima māmā i roto i ngā whare teitei. He rauemi huri pai tonu te pumice, ka taea te whakamahi hei huri i ngā rauemi whakarewa me te kōhatu; I roto i te ahumahi, ka taea hoki te whakamahi hei tātari, hei whakamaroke, hei whakakorikori, me ētahi atu. He pereki kōhatu puia taiao ngaio, he toka rangitoto me te kōhatu papara kei te hoko.