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Probably the silver ingots used in the time of Abraham may have been of a fixed weight, which was in some way indicated on them. The “pieces of silver” paid by Abimelech to Abraham (Genesis 20:16), and those also for which Joseph was sold (37:28), were probably in the form of rings.
The “piece of money” mentioned in Job 42:11; Genesis 33:19 (marginal note, “lambs”) was the Hebrew kesitah, probably an uncoined piece of silver of a certain weight in the form of a sheep or lamb, or perhaps having on it such an impression. The same Hebrew word is used in Josh. 24:32, which is rendered by Wickliffe “an hundred young sheep.”