Meteorite piece

The meteorite piece, also referred to as the rock pendant or generically just meteorite, is the main driving force behind the plot to the 1993 Super Mario Bros. film. It is a fragment of the meteor that.

Background
As explained in the film's animated introduction, it is the same meteor that killed the dinosaurs that separates Earth into two parallel dimensions; Earth and Dinohattan. While Dinosaurs become extinct on Earth, they prosper and evolve into intelligent beings in the Dinohattan dimension. Unfortunately, said dimension has poor resources and is compromised of almost entirely a barren, desolate desert. President Koopa gains control of the dimension through a military coup, with the intent of merging the two worlds. To do this, it is necessary to use a piece of the meteor that began the parallel shift to re-combine both worlds.

Super Mario Bros. film
The film begins with Daisy's mother, wife to Dinohattan's overthrown King, escaping to Earth carrying her unhatched child in an egg (as she is of reptile origin) and a piece of the aforementioned meteor in a pod. She leaves said pod outside the steps of a church, where a group of nuns take her in. The elderly nun removes the meteorite piece from the pod, causing the pod to open and reveal the egg inside. The egg hatches revealing Daisy. The elderly nun holds the meteorite piece up, which gleams as the scene cuts to twenty years later.

A now grown Daisy now bears the meteorite piece as a necklace as it is her only known connection she has to her maternal mother. She reveals during dinner with Mario, Luigi and Daniella that she has never removed it as it is all she has of her unknown past life. After dinner, Iggy and Spike kidnap Daisy to take her to Dinohattan; in an attempt to rescue her, Luigi snatches the meteorite necklace off her neck. In Koopa's Tower, President Koopa is informed by Spike and Iggy that Mario and Luigi have the meteorite piece, which he then demands them that they track them down. Upon Mario and Luigi's arrival in the Dinohattan dimension, an old lady robs Luigi of the necklace before said lady is robbed by Big Bertha. Later on, President Koopa threatens the imprisoned Mario and Luigi with de-evolution if they don't inform him where the meteorite piece is. The brothers manage to escape to Koopahari Desert, where they meet a reformed Iggy and Spike who explain the true purpose of the meteor necklace. Mario agrees to a dance with Big Bertha at the Boom Boom Bar to get close enough to her to snatch the meteorite necklace off her neck. Lena manages to take it from Mario's possession during Mario and Luigi's escape from the Boom Boom Bar. Luna, working independently from Koopa, goes to the meteorite chamber, a large contraption created by Koopa for the sole purpose of merging the dimensions. While this is occurring, Mario manages to distract President Koopa and fight him by making him think he currently has the meteorite necklace in his possession (in reality, it is a shoestring).

Lena inserts the meteorite piece into the chamber and Daisy and Luigi arrive in time to witness it. Though the insertion is successful, the power and energy generated by the meteorite kills her and Daisy realizes she was the only one that could have withstood the powers of the meteorite without dying and that is why Koopa needed her specifically. The dimensions are briefly combined into one, before Luigi and Daisy remove the meteorite once more.

Super Mario Makai Teikoku no Megami
The Super Mario Bros. film received a simplified manga retelling titled Super Mario Makai Teikoku no Megami that loosely follows the plot of the film. The manga begins explaining the backstory of a meteor strike splitting the world into two parallel dimensions and how a meteorite piece holds the power to re-unite them. Daisy is seen wearing her meteorite necklace from the start of the story, and just like in the film, it is snatched off her neck by Luigi when she is kidnapped by Spike and Iggy. At Koopa's throne, Koopa explains the purpose of the meteorite, explaining that many years ago, Daisy's mother fled with it to Earth with a newborn Daisy. Koopa demands the meteorite from Daisy, and Spike and Iggy explain to Koopa that it has been confiscated by Mario and Luigi. An enraged Koopa de-evolves Spike and Iggy into Goombas and takes to the streets of his kingdom to demand the meteorite from the brothers.

Mario fools Koopa, handing him an Exploding Mushroom tied to a string to resemble the necklace, while Luigi and Daisy flee holding the real meteorite piece. They are stopped by Spike and Iggy, who insert the meteorite into the meteorite chamber to briefly combine both worlds. Spike and Iggy die from the sheer power of the meteorite, prompting Daisy to realize only she could have withstood its force. Daisy and Luigi remove the meteorite successfully, re-splitting the dimensions.

Movie prop
It is reported that there were two meteorite necklaces in total for the filming of the movie. It was created of clear resin, which was dyed blue and bedazzled with a glittery iridescent-type liquid during the mold injection process.