Charles Ellicott Commentary 2 Samuel 12:30

"And he took the crown of their king from off his head; and the weight thereof was a talent of gold, and [in it were] precious stones; and it was set on David`s head. And he brought forth the spoil of the city, exceeding much." — 2 Samuel 12:30 (ASV)

Their king’s crown. —The same Hebrew letters, translated their king, form the name of Milcom, the chief idol of the Ammonites, and therefore some writer has quite unnecessarily supposed that the idol’s crown is meant.

A talent of gold. —If this is according to the Hebrew weights, the amount is extraordinary, for the silver talent was above a hundred pounds, the gold talent twice as much. But there were various other Eastern talents, such as the Babylonian and Persian, of much smaller weight, and it is not unlikely that a light talent may have been in use among the Ammonites. The weight, however, on any reasonable supposition, would have been too great to allow this crown to be commonly worn.