| Session Details | |
| Section | SE - Solid Earth Sciences |
| Session Title | Gem Materials in Bio- and Geosphere |
| Main Convener | Prof. Wolfgang Hofmeister (Johannes Gutenberg University, Germany) |
| Co-convener(s) | Dr. Visut Pisutha-Arnond (Chulalongkorn University, Thailand) Prof. Pornsawat Wathanakul (Kasetsart University, Thailand) Prof. Vu Xuan Quang (VAST-IMS-Hanoi, Viet Nam) |
| Session Description | Due to their macro-crystalline habit, gem minerals may be perfect objects for the investigation of geological processes and crystal growth during earth history. Ether natural chemical zoning, crystal defects or the physico-chemical relation between guest phases included within the host gems may reveal the different scales in temperature, pressure and time during the development from mobile, disordered chemical compounds to highly ordered crystals in rocks of very different background. The exact knowledge of the interaction between crystal structure, crystal chemistry and resulting physical properties of gem minerals is essential for the characterization of all kinds of crystalline solids, using their material properties, and even optimizing their properties by sophisticated enhancement and synthesizing procedures. Usually, the primary deposits of gem minerals are less valuable than the secondary deposits, which contain only that material, which is strong and homogenous enough to sustain the different ways of deposition. Nature delivers selection rules for producing placer deposits of high end materials, but the problems of exploration and exploitation of both kinds of deposits have to be solved, especially in regions of high gem mineral potential like South-East-Asia. A second group of gem materials, very prominent also in South-East-Asia, comes from the interaction of organic and inorganic substances, combined by metabolic processes of living organisms: Mother of pearl, pearls, ivory, coral and others are used as naturally grown gem material, are harvested from cultivating farms, are colour enhanced etc... Today, it is very clear that these solid products of living organisms are archives of the environment during the life of the animals. Therefore, investigations are running everywhere to develop analyzing techniques that give the data for reading in a pearl or in the shell about some parameters ruling the environment of the mussels living area. Perhaps, there are some ideas for giving a mussel a better life in a pearl farm, resulting in a better quality of pearls. |