Symbolism, Imagery, Allegory
This is the big one, folks. Silver is all up in this novel, which we would expect since Johnny is, of course, a silversmith… at least to begin with. Silver is what he loves. His skill with it is the source of his pride, and his pride is his undoing. When John Hancock comes to the Lapham house to give the order for the fatal sugar basin, he gives each of the boys a silver coin, which Mr. Lapham interprets as a bribe for votes paid in advance. Later, Johnny shows Cilla his silver cup, which also becomes an important symbol in the novel.
The most memorable moment of silver imagery comes when Johnny burns his hand:
The crucible began to settle—collapse, the silver was running over the top of the furnace like spilled milk. Something happened, he never knew exactly what. His feet went out from under him. His hand came down on top of the furnace. The burn was so terrible that at first he felt no pain, but stood stupidly looking at his hand. For one second, before the metal cooled, the inside of his right hand, from wrist to fingertips, was coated with solid silver. (2.3.22-23)
Johnny's love of silver has betrayed him. Grandpa Lapham's warning that pride goeth before a fall comes true in this case because the very thing Johnny derives his pride from causes his fall.
When Mr. Hancock later refuses to employ Johnny and sends him away, he sends Jehu after him with a purse of silver: "Johnny took the purse. It was heavy. That much copper would provide him with food for days. He opened it. It was not copper, but silver" (3.3.41). Wow, silver is good to have, but that's messed up, Mr. Hancock. As Johnny says, "I burned my hand making you a silver basin… Now, it is 'go away, please'" (3.3.38).
One of the more famous appearances of silver in literary history is found in the Bible. According to the biblical story, Judas was paid thirty pieces of silver to betray Christ, and silver has had a close relationship with treachery ever since. Many of the places we encounter silver in the novel are closely related with various types of betrayal—Dove tricks Johnny into using the cracked crucible, Mr. Hancock buys Johnny off to ease his own conscience, and Merchant Lyte snatches the silver cup from Johnny and uses it against him. (We'll talk more about that cup in a minute.)
It's significant that silver imagery gradually fades out of the novel, which indicates its decreasing place in Johnny's life.