bell
鐄 centers on a bell, specifically a large metal bell. The meaning is straightforward and concrete, referring to the object itself.
鐄 combines 金 (metal) with 黄, which likely contributes the sound. The character is a phono-semantic compound where 金 indicates a metal object and 黄 hints at the reading.
The left side is 金 (metal), and the right side is 黄 (yellow). Imagine a large yellow metal bell ringing loudly.
For コウ, picture a bell that makes a deep 'koh' sound when struck: koh -> コウ, echoing from the metal bell.