G 1198 (OTTO) Gadolinium(III) hydroxide, hydrate, 99.9% Cas 100634-91-1 - used in many quality assurance applications, such as line sources and calibration phantoms. It is used for making Gadolinium Yttrium Garnet (Gd:Y3Al5O12); it has microwave applications and is used in fabrication of various optical components and as substrate material for magneto-optical films. Gadolinium Gallium Garnet (GGG, Gd3Ga5O12) was used for imitation diamonds and for computer bubble memory. It can also serve as an electrolyte in Solid Oxide Fuel Cells (SOFCs).