Some time ago, Mr. F. C. Partridge, Mineralogist to the Geological Survey of South Africa, gave me some crystals of sapphirinc which he thought might be of interest for goniometric examination. They come from the farm Blinkwater 1037, about 47 miles NNW. of Pietersburg and 45 miles WSW. of Louis Trichardt in northern Transvaal, and were collected by him in July 1930, after he had identified some specimens of sapphirine sent to him by Mr. A. Ruskovitch of Abrasive, northern Transvaal. They occur in a coarse granitic rock rich in brown mica, and are associated with small prismatic crystals of pink corundum.
The sapphirine crystals are almost invariably tabular or platy in habit, although occasional crystals possess a rhomb-shaped cross-section. The largest crystal measures 50×35×5 mm., while the thickest one is only 7 mm. in thickness. They are generally six-sided in outline with a strong suggestion of orthorhombic symmetry.