30 tyrian schekels, at 13,8gr each = 414gr of silver. At an average purity of of 92,5% that's

300$ of today's money.

Judas betrayed Jesus for 300 bucks.

Worst trade in the history of trades, rightfully so he hung himself.

https://www.muenzen-ritter.de/45376-phoenizien-tyros-schekel-jahr-32-95-94-vchr-fvz.html