Summary: Burkeite (Na₆CO₃(SO₄)₂) is found as a surface mineral in the north of Kenya associated with thenardite and halite and in the Konya basin in Turkey associated with trona and halite. The cell dimensions of a natural burkeite are a = 7.070, b = 9.220, c = 5.173 Å. The Gibbs energy of burkeite is estimated in relation to other sodium carbonates and sulphates. Δ ΔGf,298.15° (burkeite) = 3594.2 ± 3 kJ.