This concept of a strong bond that conquers all translates perfectly to a pair of wedding bands: one in white gold to represent Riku's Mirage Split keyblade, and the other in yellow gold to represent Sora's Nightmare Break (aka Nightmare's End) keyblade.

The two individual keyblades are nearly identical but, aside from the color difference, you'll notice that the design of the handle guard is different for each keyblade: the design of the Nightmare Break's guard points up, while the Mirage Split's guard design points down. Takayas used this same design tactic to differentiate between the two rings, hugging each keyblade's half-heart and stained glass "teeth" with their respective guard design.