[s5e12] The Shiny Trinket Maneuver Official

: The episode also mentions that Amy wears a silver medical ID bracelet because she is allergic to penicillin; she notes that it is her favorite piece of jewelry.

: Mayim Bialik’s ecstatic reaction to seeing the tiara was reportedly ad-libbed, making the moment one of the show's most memorable. [S5E12] The Shiny Trinket Maneuver

"The Big Bang Theory" The Shiny Trinket Maneuver (TV Episode 2012) - IMDb : The episode also mentions that Amy wears

The primary "piece" featured in The Big Bang Theory episode (S5E12) is a tiara . : Sheldon uses it to "bribe" or apologize

After Sheldon trivializes Amy's career achievement (having her paper published in the prestigious journal Neuron ), Penny takes him to a jewelry store to find an apology gift. Sheldon eventually chooses a tiara, which leads to an iconic scene where Amy's anger instantly vanishes, and she exclaims, "I'm a princess and this is my tiara!". The Item : A sparkly tiara.

: Sheldon uses it to "bribe" or apologize for his self-centered behavior regarding Amy's accomplishment.