What kind of irony is found in "The Necklace"?
Guy de Maupassant's short story "The Necklace" follows the tragic tale of Madame Loisel, a woman who longs to be part of the aristocracy and who pays dearly for that desire. After she spends years pining away after the fancy parties thrown by those far wealthier and more important than her, Madame Loisel's husband secures her an invitation to one of these parties. Still, Madame Loisel is not happy until she has been given the money to purchase new attire for the affair and until a friend of hers (Madame Forestier) agrees to allow her to borrow a diamond necklace to wear to the party.
However, while at the party, Madame Loisel loses the necklace. Rather than come clean about her mistake, she drives herself and her spouse into financial ruin in order to pay for a replacement. It is only much later that she learns from Madame Forestier that the necklace she had lost was not made of diamonds at all—it was a fake made out of paste.
This type of irony is situational irony because the outcome of the story is very different than what Madame Loisel (or the audience) may have anticipated. The party she attends in the hopes of increasing her social standing instead ruins it. It is her obsession with wealth and social position that ultimately drives Madame Loisel into poverty and a fall from social grace—certainly the opposite of what she intended!
In The Necklace, the irony is called irony of situation. There is a great difference between what is expected and what occurs.
When Madame Loisel borrows the diamond necklace from Madame Forestier she believes that it is worth a lot of money. Therefore, when she loses it, she is stricken with the burden of what it will take to replace it, they borrow money to buy a new necklace, effectively giving Madame Forestier a real diamond necklace. They are then bound to a life of drudgery to pay back the loan. She does not know, nor do we, the reader, that the necklace is fake.
Madame Loisel and her husband work very hard to earn money to pay back the loan, believing what they did was noble and honorable. When they discover that the necklace was fake, they have wasted their time and effort put themselves into a cycle of drudgery for nothing.
In fact it is ironic that Madame Loisel longs to be rich, a fake existence really, and ends up having her life shaped by a fake necklace. Situational irony.