measure, money, coins
鍰 centers on a unit of weight or currency in ancient China: a measure, money, or coins. The meanings are closely tied to a specific historical weight standard used for metal currency.
鍰 combines 金 (metal) with 爰, which likely contributes the sound. The character originally referred to a specific weight of metal used as currency.
The left side is metal 金, and the right side 爰 looks like a hand reaching for something. Picture a hand measuring out metal coins: 鍰 is a measure of money.
For カン, imagine a can filled with ancient metal coins: can -> カン, and the can holds the measured money.