Tanzania is rich in precious gems, not least of which is the exquisite blue Tanzanite that is found nowhere else in the world. Another treasure is the Tanzanian Ruby – a glowing red stone of rare appeal. Mererani Tanzanite Mines Located in the Merelani Hills in the Manyara Region of northern Tanzania, 70 km (43 mi) south of Arusha, the Mererani Tanzanite Mines are where the blue Tanzanite was first discovered in 1968, and are still mined both by local and large mine operators today