ʻO ka pumice a i ʻole ka pumice kekahi ʻano pōhaku māmā kona waihoʻoluʻu, loaʻa i ka huʻa i hana ʻia me nā ʻōhū aniani i ka paia, a ua kapa ʻia ʻo ia he aniani lua pele silicate.
Hoʻokumu ʻia kēia mau pōhaku e ka pelemaka ʻakika ma o ka hana a ka lua pele e hoʻokuʻu aku i nā mea i ka lewa; a laila e hele i ka halihali ʻāpae a hōʻiliʻili e like me ka pōhaku pyroclastic.
Loaʻa i ka Pumice nā waiwai versicular kiʻekiʻe, loaʻa ka heluna nui o nā cell (cellular structure) ma muli o ka hoʻonui ʻia ʻana o ka huʻa kinoea maoli i loko, a ʻike ʻia ma ke ʻano he mea wehe a ʻāpana paha i ka breccia pele. ʻOiai nā minerala i loko o ka pumice he feldspar, quartz, obsidian, cristobalite, a me tridymite.
Hiki mai ka pumice ke pi’i ka pelemaka waikawa i ka ili a pili koke me ka ea o waho. Hiki i ka hu’a aniani maoli me / ke kinoea i loko o ia mea ka manawa e pakele ai a maloʻo koke ka pelemaka, mau ka pumice ma ke ʻano he mau ʻāpana i hoʻokuʻu ʻia i ka wā o ka lua pele mai ka ʻiliʻili a hiki i nā pōhaku.
Loaʻa pinepine ʻia ka pumice ma ke ʻano he hehee a i ʻole ka holo ʻana, nā mea ʻala a i ʻole nā ʻāpana i loko o nā breccias lua pele.
Hiki ke hana ʻia ka pumice ma ka hoʻomehana ʻana i ka obsidian, i pakele ke kinoea. Hana ʻia ka hoʻomehana ʻana ma ka obsidian mai Krakatoa, ʻo ka mahana e pono ai e hoʻololi i ka obsidian i pumice ʻo 880oC. Ua hāʻule ka gravity kiko o ka obsidian i 2.36 i ka 0.416 ma hope o ka mālama ʻana, no laila lana ia i ka wai. He waiwai hydraulic kēia pōhaku pumice.
He keʻokeʻo ʻo Pumice i ka hina, melemele a ʻulaʻula, ʻano vesicular me ka nui o ka puka, ʻokoʻa ka pilina o kekahi i kekahi a ʻaʻole paha i kahi hale wela me nā puka kuhikuhi.
I kekahi manawa hoʻopiha ʻia ka lua me ka zeolite/calcite. Kūleʻa kēia pōhaku i ka hau hau (hau), ʻaʻole hygroscopic (wai omo). Loaʻa nā waiwai hoʻoili wela haʻahaʻa. Ka ikaika ikaika ma waena o 30 – 20 kg/cm2. ʻO ka hana nui o nā mineral silicate amorphous.
Ma muli o ke ʻano o ka hoʻokumu ʻana (desposition), ka hoʻohele ʻana i ka nui o ka ʻāpana (ʻāpana) a me ka mea kumu, ua hoʻokaʻawale ʻia nā waihona pumice penei:
Māhele ʻāpana
Sub-aqueous
Hou ardante; ʻo ia hoʻi nā waihona i hoʻokumu ʻia e ke kahe ʻana o nā kinoea i loko o ka pele, ka hopena i ka hui ʻana o nā ʻāpana o nā ʻano nui like ʻole i ke ʻano matrix.
Ka hopena o ka waiho hou ʻana (redeposit)
Mai ka metamorphosis, ʻo nā wahi lua pele wale nō ka loaʻa ʻana o ka pumice waiwai. ʻO ka makahiki honua o kēia mau waihona ma waena o Tertiary a me kēia manawa. ʻO nā lua pele i hana ʻia i loko o kēia au honua, ʻo ia ka ʻaoʻao o ka Moana Pākīpika a me ke ala e hele ana mai ke Kai Mediterranean a hiki i ka Himalayas a laila i India Hikina.
ʻO nā pōhaku like me nā pumice ʻē aʻe he pumicite a me ka lua pele. Loaʻa i ka Pumicite ke ʻano kemika like, ke kumu o ka hoʻokumu ʻana a me ke ʻano aniani e like me ka pumice. Aia ka ʻokoʻa i ka nui o nā ʻāpana, ʻoi aku ka liʻiliʻi ma mua o 16 iniha ke anawaena. Loaʻa ka pumice ma kahi kokoke i kona wahi i hoʻokumu ʻia ai, ʻoiai ua lawe ʻia ka pumicite e ka makani no kahi mamao loa, a ua waiho ʻia ma ke ʻano o ka hōʻiliʻili lehu nui a i ʻole he sediment tuff.
He ʻulaʻula a ʻeleʻele nā ʻāpana vesicular ka lua pele, i waiho ʻia i ka wā o ka hū ʻana o ka pōhaku basaltic mai nā pele pele. Loaʻa ka hapa nui o nā waihona cinder ma ke ʻano he mau ʻāpana moe conical mai ka 1 iniha a i kekahi mau iniha ke anawaena.
Hiki i ka Pumice Indonesia
Ma Indonesia, pili mau ka noho ana o ka pumice me kekahi mau lua pele Quaternary a Tertiary. Ua uhi ʻia kona māhele ʻana i nā wahi o Serang a me Sukabumi (West Java), ka mokupuni ʻo Lombok (NTB) a me ka mokupuni ʻo Ternate (Maluku).
ʻO ka hiki i nā waihona pumice i loaʻa ka waiwai waiwai a me nā mea mālama nui loa ma ka mokupuni ʻo Lombok, West Nusa Tenggara, Ternate Island, Maluku. ʻO ka nui o nā waihona i ana ʻia ma ia wahi i manaʻo ʻia ma mua o 10 miliona tons. Ma ka ʻāina ʻo Lombok, ua hana ʻia ka hoʻohana ʻana i ka pumice mai ʻelima mau makahiki i hala aku nei, ʻoiai ma Ternate i hana ʻia ka hoʻohana ʻana i ka makahiki 1991.