The Saturn necklace (土星のネックレス,Dosei no nekkuresu) was a piece of jewelry shaped like the planet, Saturn. After having it special ordered, Tsukasa Domyoji gifted it to Tsukushi Makino. Much later, Tsukushi returned it to Tsukasa following a break-up. He tossed it into a river, but Tsukushi went to retrieve it.
Looking for a necklace in the shape of Saturn, Tsukasa Domyoji ended up having it special ordered from Bulgari. He presented it to Tsukushi Makino after showing her the planet through a telescope. Tsukushi was hesitant to accept the expensive gift at first, but allowed Tsukasa to put it around her neck. She told him "I'm happy, but there's no reason for me to accept it," but ending up keeping the necklace After moving back in with her parents, they found the necklace and made plans to sell it, until Tsukushi told them it was from Tsukasa. Having been broken up for some time, Tsukushi returned the necklace to Tsukasa, who immediately threw it into a nearby river. Unbeknownst to him, Tsukushi climbed into the river in an attempt to find the necklace. Amon Kunisawa retrieved it and handed it to her.
Despite diving into a river to retrieve the necklace, Tsukushi apparently forgot it about passing out. Amon returned it to her a few days later. Tsukushi was completely shocked that it had slipped her mind. He told her "You're not really cut out for being in love," to which she answered "Maybe."
A version of the Saturn necklace appears in Meteor Garden (2001). In episode twelve, Dao Ming Si uses a telescope to show Dong Shan Cai a meteor shower. He then tells her a romantic story, before giving her a necklace to resemble a "ring of light rays". Like the manga, Si had the necklace custom-made. After they break up, Shan Cai returns the necklace, but he throws it in a fountain. Shan Cai enters the water and retrieves it with Hua Ze Lei's help.
In the Japanese drama, Hana Yori Dango (2005), it makes its first appearance in the finale. It becomes a symbol of their relationship, appearing in Hana Yori Dango Returns (2007) and Hana Yori Dango Final (2008). Tsukasa first gets the idea to give Tsukushi the necklace, when he learns they are both "People of Saturn" from a horoscope. He later asks Rui to give it to Tsukushi along with a note. She rushes to meet Tsukasa at the airport. He puts the necklace on her, symbolizing their new relationship.
The necklace was also available for purchase at the My Margaret exhibitions in Japan in limited quantities for 10,000 yen.