Damage caused to gemstones by lasers during jewellery repair. Journal of the Gemm. Ass. of Hong Kong, Vol. 43, 23-27.
Sapphires Heated with Pressure – A Research Update. Published in InColor, Spring 2019, 86-90.
X-ray luminescence, a valuable test in pearl identification. Published in Journal of Gemmology, 2005. Author(s): H.A. Haenni, L. Kiefert, P. Giese
Asterism in beryl, aquamarine and emerald- an update. Published in Journal of Gemmology, 2004. Author(s): K. Schmetzer, L. Kiefert, H.A. Haenni
Ein neues Instrument für die analytische Gemmologie: LIBS Author(s): H.A. Haenni, M.S. Krzemnicki, L. Kiefert, J.-P. Chalain
Synthetic Verneuil corundum with unusual color zoning. Published in Gems & Gemology, 2004. Author(s): L. Kiefert