Zircon – A very old gemstone. Published in Journal of Gemmological Association of Hong Kong GAHK, 2016, 37, 37-41.
Author(s): H.A. Haenni
Colour change effects in gemstones: Causes and perception. Published in IGC 2013 Vietnam Abstract Proceedings, 110-113.
Author(s): M.S. Krzemnicki, W. Zhou, J. Maizlan
Latest research on detection of low temperature treatment of pink sapphires. Presentation by Dr. Michael Krzemnicki of SSEF.
Zircon ou zirconia à ne pas confondre. Published in Journal Suisse d’horlogerie et de bijouterie, 1989.
Author(s): H.A. Haenni
Zirconia is not zircon. Published in Swiss watch and jewelry journal, 1989.
Author(s): H.A. Haenni
Origin of the cat’s eye effect in heat-treated zircons from Sri Lanka. Published in Journal of Gemmology, 1988.
Author(s): H.A. Haenni, M. Weibel