Ko ngā pīrere karāhe whakaata rori he momo matūriki karāhe pai i hangaia mā te whakamahi anō i te karāhe hei rauemi mata, i kuruhia, i whakarewahia hoki i te pāmahana teitei e te hau māori, ka kitea i raro i te karuārai he porowhita mārama, kāore he tae. Ko tōna taupū whakaata kei waenganui i te 1.50 me te 1.64, ā, ko tōna whānui kei waenganui i te 100 maikorona me te 1000 maikorona. Ko ngā āhuatanga o ngā pīrere karāhe he āhua porowhita, he matūriki pai, he ōrite, he mārama, he ātete ki te kakahu.
Ko ngā pīrere karāhe whakaata rori hei tohu rori (peita) i roto i te rauemi whakaata, ka taea te whakapai ake i te mahi whakaata-muri o te peita tohu rori, te whakapai ake i te haumaru o te taraiwa pō, kua tautuhia mō ngā tari kawe waka ā-motu. Ina taraiwa ana te motuka i te pō, ka tiaho ngā rama o mua ki te rārangi tohu rori me ngā pīrere karāhe, kia taea ai te whakaata whakarara i te mārama mai i ngā rama o mua, kia taea ai e te taraiwa te kite i te ahunga whakamua me te whakapai ake i te haumaru o te taraiwa pō. I ēnei rā, kua noho ngā pīrere karāhe whakaata hei rauemi whakaata kore e taea te whakakapi i roto i ngā hua haumaru rori.
Āhua: ma, kāhore he tae, he mārama, he kanapa, he porowhita, kāhore he mirumiru, he poke rānei e kitea ana.
Porowhita: ≥85%
Kiato: 2.4-2.6g/cm3
Taupū whakaata: Nd≥1.50
Hanganga: karāhe houra raima, te ihirangi SiO2 > 68%
Te mātotoru o te papatipu: 1.6g/cm3