silicate

Silicon-based life form. They were first discovered after the Canary Incident, although no causal relationship has been established. Attempts to communicate with them have been largely unsuccessful, usually cryptic, and occasionally fatal. As far as anyone can tell, silicates are completely peaceful toward carbon-based life forms when left alone, if you consider lethal indifference to be peaceful. If you do manage to provoke them, they're somewhat less indifferent.