The Diamond Communicator is an octahedral object that first appeared in "It Could've Been Great".
It was later revealed to be a communicator in "Message Received", offering direct contact to any member of the Great Diamond Authority through the Diamond line. The communicator from the Moon Base was destroyed in the same episode by Yellow Diamond through its remote detonation feature.
The Diamond communicator is an octahedral object with the facets colored white, light yellow, light blue, and light pink with each color representing an individual Diamond member.
To be activated, the communicator must be twisted 180°. After selecting a color, it will then send a signal to the chosen Diamond and project a screen. The camera will record the visual and audible activity of the user and the chosen Diamond's headquarters.
In "Message Received", Peridot reveals it to be a communicator that could contact any of the Diamonds. Later on, Peridot makes contact with Yellow Diamond through the device. Peridot terminates her allegiance to her after an argument and cuts off the communication. Yellow Diamond responds by detonating the communicator remotely, but it was bubbled by Steven and knocked away by Garnet before the blast could hurt anybody.
In "Back to the Moon", it is mentioned when the Ruby Squad came to the Moon Base with the Crystal Gems, only to find the communicator gone and the panel smashed thanks to the events of the Gems' previous visit, preventing them from contacting Yellow Diamond.
- It can be assumed that the Diamond Communicator's use is reserved solely for the Diamonds or at least high ranking gems because Yellow Pearl referred to it as the "Direct Diamond Communication Channel"
- The communicator's signal is extremely strong as the transmission can travel across beyond the moon all the way to Homeworld.
- The Diamond Communicator can be remotely detonated and cause a potent explosion, as shown in "Message Received".
- The base in "Jungle Moon" has no mention of a Diamond Communicator.