Synthetic Ametrine
Vladimir S. Balitsky1, Tijin Lu2, George R. Rossman3. Irina B. Makhina1, Anatolii A. Mar'in1, James E. Shigley2, Shane Elen2, Boris A. Dorogovin4
1Institute of experimental Mineralogy, Chernogolovka, Russia
2Gemological Institute of America, Carlsbad, California, USA
3Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena,
California, USA
4Russian Reseaerch Institute for Mineral Synthesis, Alexandrov, Russia
Abstract
Gem quality synthetic ametrine has been
produced commercially in Russia since 1994, by hydrothermal growth from
alkaline solutions. Faceted synthetic ametrin has many similarities to
its natural counterpart from Bolivia. For the most part, however, the
synthetic ametrine obtained for this study could be identified by a
combination of characteristics, including growth features such as
twining and oclor zoning. EDXRF chemical analyses revealed higher
concentrations of K, Mn, Fe, and Zn tha in natural ametine. IR spectra
of the synthetic citrine portions showed more intense absorption in the
3700-2500 cm-1 range compared to natujral ametrine; the synthetic amethyst zones showed a weak diagnostic peat at 3543 cm-1.
Gems & Gemology, 35, 122-134