ʻO ke kila Corten kahi papa o ke kila kila, ma hope o nā makahiki he nui o ka hoʻolaha ʻana i waho e hiki ke hana i kahi papa ʻōpala ma luna o ka ʻili, no laila ʻaʻole pono e pena ʻia ka pale. ʻO ka hapa nui o nā kila haʻahaʻa haʻahaʻa e ʻā a ʻino paha i ka wā i ʻike ʻia i ka wai i ka wai a i ʻole ka ea. Lilo kēia ʻōpala ʻōpala a hāʻule mai ka ʻili metala. He kūpaʻa ia i ka corrosion i ʻike ʻia e nā mea hao haʻahaʻa haʻahaʻa.
Ke pale nei ke kila Corten i nā hopena ʻino o ka ua, ka hau, ka hau, ka noe, a me nā kūlana ʻē aʻe ma o ka hana ʻana i kahi uhi hoʻoheheʻe ʻeleʻele ma ka ʻili metala. ʻO ke kila Corten kahi ʻano kila me ka phosphorus, keleawe, chromium, nickel a me molybdenum. Hoʻomaikaʻi kēia mau alloys i ke kūpaʻa ʻino o ka lewa o ke kila ma ka hana ʻana i kahi papa pale ma luna o kona ʻili.
ʻAʻole kūʻokoʻa ke kila Corten, akā i ka wā ʻelemakule, loaʻa iā ia ke kūpaʻa corrosion kiʻekiʻe (e pili ana i ka pālua o ke kila kalapona). Ma nā noi he nui o ke kila hoʻoheheʻe ʻana, ulu maoli ka papa ʻōpala pale ma hope o 6-10 mau makahiki o ka ʻike maoli ʻana i ka mea (e pili ana i ke kiʻekiʻe o ka ʻike). ʻAʻole haʻahaʻa ka nui o ka corrosion a hiki i ka hōʻike ʻia ʻana o ka hiki ke pale o ka papa ʻōpala, a e hoʻohaumia ka ʻeleʻele uila mua i kona ʻili ponoʻī a me nā wahi ʻē aʻe e pili ana.