Material recovered from @The Silence sites is collectively referred to as Silence substance. This term covers several apparently related materials whose composition cannot be fully determined using conventional analysis.
Silence substance may shift between solid, liquid, and energy-like states without predictable changes in temperature or pressure. It can remain completely inert for years, then react suddenly to a particular person, machine, signal, or location.
Prolonged exposure has caused hallucinations, memory loss, neurological damage, equipment failure, and death. In a very small number of cases, exposure has instead produced permanent changes in human perception and cognition.
These survivors are known as @Resonants.