The necklace is certainly the primary symbol in Guy de Maupassant's short story "The Necklace." The necklace is a symbol of pride throughout the story, though the meaning of that word changes by the end.
Mathilde Loisel is an unhappy woman, discontent for most of her life because she always felt as if she should have more and better.
She suffered endlessly, feeling herself born for every delicacy and luxury.
It is clear from the story that she was not really poor or underprivileged, or she would have had nothing to give up when the Loisels' circumstances change; however, she sees her life that way because she is so discontent.
When her husband brings home an invitation for a ball, he assumes Mathilde will be thrilled; instead she is even more unhappy than she was before because she feels as if she has nothing suitable to wear. Even after her husband makes a sacrifice and get her a dress, Mathilde wants more.
She wants fine jewelry to match her new dress, so she visits her friend Madame Forestier and borrows a lovely diamond necklace which she assumes is real (though if she had been less self-absorbed she might could have figured out it was a fake). She attends the ball with such excessive pride that she ditches her husband and does exactly what she pleases because this is her night, the night she finally deserves.
That necklace is the symbol of her excessive pride, and it gets worse right after she loses it. Mathilde is much too proud to tell her friend that she lost the necklace, so she and her husband are forced to borrow outrageously in order to replace it. For the next ten years, the two of them work hard, really hard, to pay back what turned out to be unnecessary loans. During this time the Loisels really do live as she had always felt they were living; it is mean and unpleasant, but Mathilde learns a few valuable things.
In that decade of work and sacrifice. Mathilde learned how to be content with much less. Her appearance has changed, as well, and Madame Forestier barely recognizes her when the two women meet one day. Mathilde finally shares the truth that the necklace she returned was a replacement, but she and her husband have finally paid off the debt. Of course the great irony is then revealed: the original necklace was not real.
By the end of the novel, it is clear that Mathilde has come to appreciate the value of hard work and sacrifice, so the necklace at the end of the story is symbolic of a different kind of pride--pride in herself and her husband for working hard, pride in finishing a task and accomplishing a goal, even pride in what she and her husband have, something she would never have felt before losing the necklace.
From excessive, arrogant pride to the pride of accomplishment in a job well done, the necklace remains a symbol of pride in this story.