Dictionary. Duroc-Danner, J. M. Untreated yellowish orange sapphire exhibiting its natural colour (PDF). Journal of Gemmology. 2011, 32: 175–178 [2016-12-13]
leaves are 10-50mm long x 5-40mm across with an acute tip and glossy green colour. The flowers are red or yellow and there are usually 1–5 on the side shoots
03.052. Mineral Galleries Faye, G. H.; Nickel, E. H. On the origin of colour and pleochroism of kyanite (PDF). The Canadian Mineralogist. 1969, 10: 35–46