The lava at Ol Doinyo Lengai is cool enough that it only glows at night.
The lava produced at Ol Doinyo Lengai is unlike any other lava on earth. Most volcanoes produce basaltic lava, but Ol Doinyo Lengai is the only one in the world that produces natrocarbonatite lava – a type of lava rich in the rare sodium and potassium carbonate minerals – nyerereite and gregoryite. These minerals are quite uncommon in the geologic record, and even less common at the surface as a liquid. Due to this unusual composition, the lava is erupted at relatively low temperatures – approximately 500-600 °C, which is half the temperature of typical glowing basaltic lava.
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