1. Anderson, B., J. Payne. 2006. The Spectroscope and Gemmology. Nashville, Tennessee, GemStone Press, 288 p.
2. Dedeyne, R., I. Quintens. 2007. Tables for Gemstone Identification. Gent, Glirico, 309 p.
3. Dominy, G. M. 2013. The Handbook of Gemology. Palma, Mallorca, Amazonas Gem Publications, 654 p.
4. Gilbertson, А. 2016. Value factors, design, and cut quality of colored gemstones (non-diamond). ‒ The GemGuide, January/February, 1–31.
5. Guenther, B. 1991. Tables of Gemstone Identification. Kirschweiler, Verlagsbuchhandlung E. Lenzen, 207 p.