Stargate SG-1, Ancients DHD Control Crystals

original movie prop

The Ancients created the first known crystal control technology, and used it to operate their Stargates and related instrumentality. In the Milky Way Galaxy, surviving Ancient control crystals are generally found in the form of colored faceted rods and spires, with this form now widely adapted and modified by other races for their own use. These particular crystals are of the type used in the Ancients supercomputer platform known to the Tau'ri of Earth as a Dial Home Device or DHD (used to operate a Stargate), and best seen onscreen inside a disassembled DHD in seventh season episode Avenger 2.0.

3" (7.6 cm) 8-sided translucent acrylic crystal rods, in two colors. 

From Legends Memorabilia.