Cyanogen silicate was a chemical compound utilized in medicine by doctors and healers of both the Galactic Republic and the Old Sith Empire. The Sith species' Massassi warrior caste used the compound as a powerful cauterizing agent, and the Human Seelah Korsin framed Ravilan Wroth and his fellow Sith for the deaths of a hundred thousand native Keshiri on the planet Kesh whom she had poisoned with cyanogen silicate. Over a thousand years later, the xenopathologist Archiban Kimble used cyanogen silicate as part of his cure for a flesh-eating disease.
A chemical compound, cyanogen silicate was used as a cauterizing agent in its solid form to heal the wounds of the Massassi warrior caste of the Sith species, as their tough hides proved resistant to treatment by other agents. However, the compound became incredibly deadly when exposed to moisture, killing members of the Human, Keshiri, and Sith species within minutes after exposure, regardless of whether it was ingested or simply touched. Moisture also broke down the compound as it intensified its effects, which meant that a single particle per billion could kill hundreds of people if it was inserted into a settlement's water supply.
Cyanogen silicate was used by the Sith Empire as a cauterizing agent as early as the Great Hyperspace War with the Galactic Republic in 5000 BBY, and the Sith starship Omen carried a supply in its sick bay before crashing on the planet Kesh that year. One of the deck plates in the wreckage became stained with cyanogen silicate, and the Keshiri Gorem came into contact with the contaminated plate while he searched the crushed sections of the ship. Even though he washed his hands, Gorem died minutes afterward—he only survived long enough to exit the wreckage of the Omen before he collapsed.
The Human Seelah Korsin had a supply of the compound on the Omen, as did the ship's Sith pureblood quartermaster, Ravilan Wroth, and, in 4985 BBY, Wroth used the compound to poison the aqueducts of the native Keshiri's city of Tetsubal. Wroth hoped to use the massacre of Tetsubal's inhabitants to convince the other survivors of the Omens crash that they should separate themselves from the Keshiri population and concentrate on how they would escape the planet. However, Korsin deduced Wroth's hand in the events at Tetsubal, and she ordered her personal aide, Tilden Kaah, to use Korsin's own supply of cyanogen silicate to poison several other local water supplies and thereby frame Wroth and his fellow Sith survivors for the massacres. Korsin's plan worked, causing the deaths of a hundred thousand Keshiri, and it resulted in the purge of all pureblood Sith from Kesh.
Around 3642 BBY, over a thousand years later, cyanogen silicate was a known compound in the Galactic Republic, and the xenopathologist Archiban Kimble—better known as Doc—acquired supplies of cyanogen silicate, ardanium, and accellerite in his work to cure a rare flesh-eating disease that afflicted the Hutt Suudaa Nem'ro. He brought the chemicals aboard the ship of his ally, the Jedi Knight known as the Hero of Tython, and completed the mixture there.
Cyanogen silicate first appeared in John Jackson Miller's 2010 eBook Lost Tribe of the Sith: Paragon.