"Bubbling" is the process where a Gem encases a specific object inside a bubble via contact or energy projection, and either takes it with them or transfers it to a different location. Items and Gems that are bubbled remain inactive until released.
Steven bubbling Centipeetle's gemstone.
When a bubbled Gem is released, it instantly regenerates with seemingly no mental problems or awareness of their time contained as seen with the Centipeetle Mother and Peridot. However, the Centipeetle is unable to take the form it wants to assume (shown by its initial hologram), and the actual body it generates is much smaller than the preview. As no such thing happened with Peridot, who is only bubbled for a short time, one can infer that energy is drawn from these Gems over a long period of time. Whether this process is carried out by the temple or from the bubble itself is currently unknown.
Process
The gem selects an object that they wish to encase inside the bubble, and concentrates to create a bubble that can surround the object. With experience, this process becomes much more instinctual, shown by how easily gems like Garnet are able to do it. The resulting bubble is a different hue based on the type of gem that bubbled it, and has unusual properties. These bubbles are able to float, hence their chosen name, and are able to support Steven as shown in "Monster Buddies" but can be moved with ease as shown in "Catch and Release". Bubbles are significantly stronger than natural bubbles, and can remain intact for an incredibly long period of time undisturbed. However, bubbles can be popped very easily by outside forces. The majority of bubbles are seen in the Crystal Temple inside The Burning Room, although due to the fragility of bubbles only Garnet is allowed inside of it. After bubbling an item, the holder can either keep it in their possession or teleport it to a different location via physical contact. It is assumed that this teleportation ability works on bubbles only, and operates on a sort of previously set waypoint system, as the only known receiving location is The Burning Room, and Steven is able to send the Centipeetle there on his first attempt. In "Kindergarten Kid", it is revealed by Steven that bubbles can be teleported by tapping the top of the bubble and it is implied that this bubble teleporting possess an innate "homing" capability that causes the bubble to teleport to what ever place the Gem who created it considers home, as Peridot's bubble is shown being transported to The Barn, instead of The Burning Room.
Purpose
The purpose of bubbling a gem is to contain its gemstone and prevent it from generating a new physical form. In the main series, this process is used solely on gems the Crystal Gems deem dangerous, as Peridot is bubbled just like any other corrupted gem. The series suggests these bubbled gemstones may have another purpose, which is hinted at on many different occasions. The most notable of these include the lung-like structure of the Burning Room, the fact that Peridot referred to the process as "gem harvesting", and the significantly dwarfed state of the Centipeetle Mother after spending time bubbled in the room. All of these events strongly suggest that energy is being harvested from the gems contained in the room in a way similar to how air is processed and pushed through a human body (hence the lung-like design of the room), although the purpose of this hypothetical energy collection process is still unknown.
Trivia
- It is unknown if all Gems possess the ability to bubble objects.
- Garnet is able to bubble gems with and without her gauntlets which implies that Gems don't always need physical contact to bubble gems.
- In "Gem Drill", Steven bubbles the Cluster without making physical contact with it.
- An active object or person is capable of bursting the bubble from the inside, as demonstrated in "Monster Buddies" and "Message Received".
- There is an apparent size limit to what can be bubbled, as demonstrated by Pearl's and Peridot's incredulity to the prospect of bubbling the entire Cluster in "Gem Drill".
- Gem Shards have the ability to bubble even without their physical form, as shown in "Gem Drill".
- Peridot is horrified at the concept of being harvested in "Catch and Release", implying that the process causes lasting or permanent harm to any gem involved. However it is likely Peridot was simply mistaken as to the purpose of the Bubbled Gems found within the Burning Room.
- In "Kindergarten Kid", it is revealed that Bubbled Gems (and presumably other bubbled objects) are transported to which ever place the Gem that bubbled them considers to be "home" when they tap the top of the bubble, as Peridot's are shown going to The Barn, instead of The Burning Room.