High Pressure Hydroghermal Growth of Beryl Single Crystals

Research Project

Project/Area Number	61470066
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	無機工業化学
Research Institution	Hokkaido University
Principal Investigator	KODAIRA Kohei Fac.of Engineering,Hokkaido University, 工学部, 教授 (60002002)
Co-Investigator(Kenkyū-buntansha)	HIGUCHI Mikio Fac.of Engineering,Hokkaido University, 工学部, 助手 (40198990) SHIMADA Shiro Fac.of Engineering,Hokkaido University, 工学部, 助教授 (90002310)
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥6,700,000 (Direct Cost: ¥6,700,000) Fiscal Year 1987: ¥700,000 (Direct Cost: ¥700,000) Fiscal Year 1986: ¥6,000,000 (Direct Cost: ¥6,000,000)
Keywords	High pressure hybrothermal arowth / Internal heating autoclave / ベリル単結晶 / 単結晶 / ベリル / 高圧水熱法
Research Abstract	Beryl crystals were grown from nonequilibrium state by dissolution-precipitation of each starting powders.Under high pressure hydrothermal conditions,crystal growth was observed at 500゜ー650゜C and 0.1-0.3N NaOH solutions.Clear and smooth beryl crystals were grown from the most suitable condition at 600゜C and 0.1N NaOH solution.Representative P(101^^-1)face for hydrothermal growth was developed.The P(101^^-1)fece seems to have relatively high growth rate comparing with that of other m(101^^-1)and c(0001) faces. In the IR spectra of the beryl crystals obtained from 0.1-0.3N NaOH solutions, two sharp stretch at 3690 and 3580 cm^<-1> were observed.There are large differences in the IR spectra of synthetic hydrothermal emeralds and that investigated by the present beryl,both of which show a sharp OH stretch band at 3690 cm^<-1>. In addition this band, high pressure hydrothermal beryl exhibits a sharp band at 3580 cm^<-1>,Hich is the same as the natural Colombian emerald.The high pressure hybrothermal beryl can not be distinguished with natural ones.The channel was also somewhat large for the direction of a-axis in the present beryl comparing with the emeralds grown by flux method on account of alkali cations and wster.The refractive index and densities were clearly large so as to be in natural emeralds.