This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鏆 combines 金 (metal) with 貫, which likely contributes the sound. The exact historical development is uncertain.
The metal radical 金 suggests something metallic, and 貫 hints at piercing or a string of coins. Picture a metal bracelet or a tool for piercing, but the exact meaning is unclear.
For カン, imagine a metal can (カン) with a string of coins 貫 inside: can -> カン.