Role in the film
At the engagement party that Grandmother Fa organized, Zhou and Li could see that Mulan and Shang weren't in balance as they thought since their answers for the guests' questions were different from each others'; so they decided to give their wedding gift to them a bit earlier they had planned. Not long after the happy couple got word from the Emperor and were getting ready to ride off and met with him, Zhou and Li told them the importance of balance with the sun and rain to make the flowers of their blossom tree grow and bloom they took off the necklaces from around their necks and put the Yin-Yang pieces together as they showed it to them. Mulan was a little surprised that her parents were giving them their necklaces before Li told them that they were once worn by their great-grandparents and were now being given to them. Li placed the Yang necklace around Mulan's neck while Zhou gave the Yin necklace to Shang, so they may become like sun and rain as they build their future together and be in balance with their differences.
When they embraced each other after apologizing for their shot, earlier fight, the two necklaces got tangled up with each other until Mulan untangled them. Mulan and Shang look at their necklaces when they are thinking about their feelings for each other and what Zhou had told them before they left for their mission, as they question rather or not if they were too different to be happy together.
Later on, when Shang was found by his horse and pulled out of the river, his necklace was still around his neck. Shang had even clutched it in his hand as he thought about Mulan's point of view with forced marriages, before riding off to save her from marrying a man she doesn't love so she could complete the mission.
- The necklaces are modeled after the symbol Yin and Yang, a principle that illustrates contrary forces as being interconnected, and give rise to each other. However, each half was owned by the wrong people—Mulan and Li had the white piece (Yang), which associated with masculinity, and Shang and Zhou had the black piece (Yin), which associated with femininity.
- This trait is shared with the coat colors of Mulan and Shang's respective horses, though with the correct colors associated.
- They are the second piece of jewelry that Mulan received from her family for a special occasion: the first being a flower styled hair slid that Li gave Mulan for her meeting with the Matchmaker.