Unknown Bubbled Object

The "unknown bubbled object" is an object that floats inside Lion's Dimension. It likely belonged to Rose, as she was the only one with access to it and it sits next to her other belongings.

Appearance
It appears hollow and has a shape similar to that of an upside down mesoamerican step pyramid, being approximately the size of Steven's head. Seeing as how Gem Bubbles don't distort the color of objects inside (despite having a tinted exterior), the object is likely pink. Because of that and the small swirly protuberance on the inside, the object slightly resembles a rose.

Trivia

 * It strongly resembles a pyramidal form of the element Bismuth, which has in traditional alchemic studies and media been seen as an infinite "seed" for creating new environments. It can also exhibit many colors, including the white, yellow, and blue seen in this symbol.
 * Given its shape, it might serve a similar purpose to the key used by Garnet to open the Pyramid Temple in "Serious Steven." As seen here and here.
 * Since it's (likely) rose colored and rose shaped, the object probably has some connection with Rose.
 * Gem Bubbles have been used almost exclusively to contain Gems so far, so the object may be a Gem.