There are several methods of growing crystals. We often use the "Bridgman technique":
The starting material, a powder, is filled into a quartz ampoule, sealed under high vacuum, put into the Bridgman furnace and heated. When the melt is homogeneous, the furnace is slowly moved upwards. Thus the melt is cooling, the narrow tip of the ampoule always being the coldest point. Crystallization will start there, and finally (usually after 10-14 days) the ampoule is filled with one single crystal.

Idea for picture: Karl Krämer

Last modified: 13.12.11 by Gabriela Frei