|Featured In||The Stormlight Archive|
The Soulcaster consists of two rings and a bracelet, with chains connecting them. Three extremely large oval-cut gemstones–a smokestone, a diamond, and a ruby–are set in a triangle that lays across the back of the hand. The gems grow brightly with Stormlight when Jasnah is Soulcasting. Jasnah sometimes wears a fingerless glove over the Soulcaster to block the light from the gemstones.
Jasnah's use of the Soulcaster exacerbated her conflict with the Vorin Church, as they maintain a monopoly on the use and control over Soulcasters, and her Soulcaster was to all appearances, the only Soulcaster outside their control. This monopoly is likely in order to protect the secrets of the Soulcaster - including the toll it takes on the user. The Church also believes the Soulcasters to be holy objects and gifts of the Almighty, which is one justification they use to try to take the Soulcaster away from Jasnah.  Many members of the church have attempted to remove the Soulcaster from her possession - either through bribery, coercion, or theft. 
Jasnah's open and notorious use of the Soulcaster made her the only viable target for Shallan Davar, who needed to steal a functional Soulcaster to return to the Ghostbloods as a replacement for the broken Davar Soulcaster. Shallan steals the Soulcaster before later finding out that it is a fake.
Jasnah's Soulcaster is thought to be a very powerful version of the fabrial. However, it could not actually Soulcast any of the essences, as it was essentially a hollow shell. The gems within were used by Jasnah as a repository of Stormlight that fueled her own Soulcasting.