This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鈖 combines the metal radical 金 with the phonetic component 分. The exact historical development and original meaning are uncertain.
Since the meaning is unclear, focus on the shape: metal 金 beside division 分. Imagine dividing a piece of metal into parts.
For フン, picture a fun experiment where you divide metal with a saw: fun -> フン, and the metal splits apart.