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addition, spindles and irregular forms of coarse-grained massive chromite may be found set in fine-grained chromite. In the nodular type, the nodules may be spherical to oval, and vary in diameter f om 3 mm to 2 cm. At one outcrop, nodules occur in clusters. Nodular and chromite-net (Thayer, 1969) textures may occur side by side in the same ore body. Chemical analyses of seven samples of purified chromite presented in Table I show that they contain 39.o6 ~o to 50"66 ~o Cr203 and their Cr/Fe varies from 2.o6 to 2.53. This, together with the reciprocal relationship between Cr203 and A120 3 (fig. 2), non-relationship between Cr203 and total iron and a below-16 total iron content (Thayer, 197o) shows that these chromites are chemi-cally comparable to most other refractory grade podiform chromites of the world, such as those described by Thayer (1969, I97o), Zachos (x964), Hutchison (I972), and Jackson and Thayer (1972). Plots of the seven analyses (fig. 3) on the triangular diagram of Stevens (1944) show that six belong to the 'aluminian chromite ' field and one to the 'chromian spinel ' composition range. None could fall in the metallurgical grade. These chromites are more aluminous than the chromites of the alpine type Zhob Valley igneous complex of Pakistan, most of which are of high-chromium type and metallurgical grade (Ahmad, 1972; Bilgrami, 1963; Bilgrami and Ingamells, 196o). Reflectivity, micro-hardness, and unit cell edge determinations are also reported in Table I