Description of the Corundum Stone, and Its Varieties, Commonly Known by the Names of Oriental Ruby, Sapphire, with Observations on Some other Mineral Substances

C. de Bournon
1800 Proceedings of the Royal Society of London  
other mineral substances with observations on some of oriental Ruby, Sapphire, &c. commonly known by the names stone, and its varieties,
doi:10.1098/rspl.1800.0051 fatcat:2lxnui3hireabk4otpdyu3jvpi