Definition and Usage in Scripture:
"Pieces of silver" in the Bible typically refer to units of currency used in various transactions and significant events throughout biblical history. The term often denotes a specific weight or value of silver, which was a common medium of exchange in ancient times.

Old Testament References:
1. Joseph Sold by His Brothers: One of the earliest mentions of pieces of silver is in the account of Joseph being sold by his brothers. In Genesis 37:28 , it states, "So when the Midianite merchants came by, his brothers pulled Joseph out of the cistern and sold him for twenty pieces of silver to the Ishmaelites, who took him to Egypt." This transaction highlights the betrayal and the value placed on human life in that era.

2. Temple Tax and Offerings: In Exodus 30:13 , the Israelites are instructed to give a half shekel as an offering to the LORD, which is described as "twenty gerahs to the shekel." This offering was a form of temple tax, illustrating the use of silver in religious obligations.

3. Redemption and Valuation: Leviticus 27:3-7 provides guidelines for the valuation of persons dedicated to the LORD, with specific amounts of silver assigned based on age and gender. This reflects the societal norms and economic practices of the time.

New Testament References:
1. Betrayal of Jesus: Perhaps the most infamous mention of pieces of silver is in the context of Judas Iscariot's betrayal of Jesus. Matthew 26:14-15 records, "Then one of the Twelve, the one called Judas Iscariot, went to the chief priests and asked, 'What are you willing to give me if I hand Him over to you?' And they set out for him thirty pieces of silver." This act fulfilled the prophecy found in Zechariah 11:12-13, where thirty pieces of silver is the price set for the shepherd.

2. Return and Use of the Silver: After realizing the gravity of his betrayal, Judas attempted to return the silver. Matthew 27:3-5 narrates, "When Judas, who had betrayed Him, saw that Jesus was condemned, he was filled with remorse and returned the thirty pieces of silver to the chief priests and elders." The chief priests used the returned silver to buy the potter's field, as described in Matthew 27:6-7 , fulfilling another prophecy.

Cultural and Theological Significance:
Pieces of silver in the Bible often symbolize betrayal, greed, and the value of human life. The use of silver in transactions, offerings, and valuations reflects the economic and cultural practices of ancient Israel and the surrounding regions. Theologically, the thirty pieces of silver associated with Judas's betrayal have become emblematic of treachery and the fulfillment of divine prophecy.

Conclusion:
The term "pieces of silver" carries significant weight in biblical narratives, serving as a medium of exchange and a symbol of deeper moral and spiritual truths. Its repeated use in both the Old and New Testaments underscores its importance in understanding the economic, cultural, and theological contexts of the biblical world.