Tenkara

Tenkara was a class M planet situated between Federation and Klingon territories in the mid 23rd century, and the homeworld of the Tenkaran race.

Tenkara was one of the few planets in its sector with significant mineral resources, including dilithium, making it a strategic location for slowing the Klingon Empire's expansion. To that end, the Federation agreed in 2264 to help the Tenkarans mine these resources, and two years later, to place a Starfleet security detail there, near the capital city of Kurpol. (TOS short story: "Official Record")