白+金 HAKU, BYAKU, shiro(i), shira - white / KIN, kane - gold
鐵 TETSU, TECHI, kane, kurogane - iron
水+銀 SUI, mizu - water / GIN - silver
鉛 EN, namari - lead
沃+素 YOU, soso(gu) - pour / SO, SU - element, naked, simple
They all represent chemical elements.
白金 HAKKIN - platinum
鐵 TETSU, TECHI, kane, kurogane - ironTETSU, TECHI, kane, kurogane - iron
水銀 SUIGIN - mercury
鉛 EN, namari - lead
沃素 YOUSO - iodine