The Halkans were a humanoid race native to the planet Halka. They were noted for their extreme pacifism. In 2267, the Halkans refused to open negotiations with Captain James T. Kirk when he attempted to negotiate Federation mining rights for the dilithium sources located on Halka. The refusal was based on the fear that the mined dilithium would then be used for acts of violence. (TOS episode: "Mirror, Mirror")