This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鍴 combines 金 (metal) with 耑, which likely contributes the sound. The exact historical development is uncertain.
The left side is metal 金, and the right side 耑 resembles a sprout or tip. Picture a metal tool with a sharp tip, but its exact use is unclear.
For タン, imagine a tan metal tool: tan -> タン, and the metal 金 side shines with a tan color.