This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鏺 combines 金 (metal) with 發, which likely contributes sound. The exact historical development is uncertain.
The left side is metal 金, and the right side 發 suggests releasing or sending out. Imagine a metal tool used for cutting or scraping, but its exact use is unclear.
For ハツ, picture a metal hatchet (hatchet -> ハツ) with the metal 金 side and the 發 shape as the handle.