Albert Barnes Commentary 1 Kings 21:2

"And Ahab spake unto Naboth, saying, Give me thy vineyard, that I may have it for a garden of herbs, because it is near unto my house; and I will give thee for it a better vineyard than it: or, if it seem good to thee, I will give thee the worth of it in money." — 1 Kings 21:2 (ASV)

I will give you the worth of it in money - literally, “I will give you silver, the worth of it.” Money, in our sense of the word, that is to say, coins of definite values, did not yet exist. The first coin known to the Jews was the Persian daric, with which they became acquainted during the captivity (1 Chronicles 29:7 note).