gems, pyroxene, orthopyroxene, enstatite, Kenya, East Africa, John Saul

Enstatite of yellowish-green colour from the region of the Mairimba Hill, Kenya, is described. The crystals have refractive indices of nx = 1.652, nz = 1.662, β = 0.010 and a density of 3.23 g/cm³, and owe their attractive colour to a content of 1.45% FeO and 0.22% Cr₂O₃.