Silver is mentioned 320 times in the KJV translation. In the Middle East, before 500 B.C., it was harder to find than gold. This may be why, when the Bible comments on Abraham's wealth (Genesis 13:1 - 2, 24:35) or what the Israelites took from the Egyptians (Exodus 3:22, 11:2), silver is listed before gold.
Silver was used as a method of exchange (in the form of bars and other shapes) as early as the 1900s B.C. during the life of Abraham (Genesis 13:1 - 2). It was used, especially among common people, as a means to buy and sell goods far more frequently than gold.
This precious metal lends itself to a whole host of uses. Jewels and jewelry made from it were among the many gifts Abrahams's steward gave to the woman who would become the wife of his son Isaac (Genesis 24:53). The couches of rulers were made from it (Esther 1:6), as well as dishes, bowls, candlesticks and even musical instruments (Numbers 7:13, 1Chronicles 28:15, Isaiah 30:22).

The children of Israel, before they were led out of Egypt's bondage by Moses, were commanded to take things containing this metal from the Egyptians (Exodus 3:22, 11:2, etc.). Silver was used extensively in Israel's tabernacle in the wilderness (Exodus 26:19, 38:27, Numbers 7:13) as well as the permanent temple in Jerusalem (2Samuel 8:11, 1Kings 7:51, etc.). Pagan idols were also created out of silver (Exodus 20:23, Isaiah 30:22, Hosea 13:2).
Haman, the prime minister of Persia under King Xeres (Esther 3:1), was willing to pay 10,000 talents of silver (roughly $153 million U.S.) to cover the expenses of exterminating all Jews in the land.
An Ephesian craftsman named Demetrius made and sold idols of the goddess Diana. Concerned that his lucrative silver business would suffer loss as people began to worship the true God, he stirred up fellow craftsmen in the city against the apostle Paul (Acts 19:23 - 41).

This metal can also symbolize in the Bible a kingdom that is inferior to one that is greater (see Daniel 2). It can represent great wealth and abundance as was seen during the reign of Solomon (1Kings 10:27). God's refining of the hearts of people is likened to the refining of this metal (Psalm 66:10, Isaiah 48:10). The words of truth that come from the Eternal are said to be like this metal refined seven times (Psalm 12:6).
This precious metal has and will play a significant role in fulfilling Biblical prophecy. King Nebuchadnezzar dreamed about a great statue that had a head made of fine gold along with a chest and arms of silver (Daniel 2:32 - 33) which symbolize world empires.
Judas was paid thirty pieces of this metal for betraying Christ (Matthew 26:14 - 16, 27:9). The prophet Zechariah prophesied that this precious metal would ultimately be used to buy a potter's field (Zechariah 11:12 - 13).
As an interesting side note, it is likely that the thirty pieces of this precious metal paid to Judas Iscariot were made in Tyre. It was the nearest city to Jerusalem that consistently made large quantities of coins from the metal.
Those who place a higher value on things made of silver rather than on repentance are condemned in the Bible (Revelation 9:20). Those who, when the devil rules the earth, grow wealthy from it will be made to "weep and mourn" when God destroys their ability to gain riches (Revelation 18:9 - 12).