Lake Natron

Lake Natron is a large, shallow soda lake with waters saturated in sodium carbonate. Although it appears hostile to living creatures, it is far from lifeless: it is home to an endemic fish species, the alkaline tilapia, and to a micro-organism, spirulina, on which lesser flamingos feed — the lake is their principal breeding site in Africa.
Lying in a depression of the Great Rift Valley in northern Tanzania, Lake Natron sits northwest of the extinct Gelai volcano and close to the active Ol Doinyo Lengai, the Maasai's sacred mountain. At an altitude of around 2,880 m, Ol Doinyo Lengai is unique for the nature of its lava: it is the only volcano in the world to emit natrocarbonatite. This highly fluid lava, with a relatively low temperature (around 510°C), is black when it erupts and turns white as it cools.