Bismuth Germanate is an intrinsic scintillation material with high absorption power

Technical parameters

Physical properties 
Density 7.13 g/cm3
Hardness by Mohs 5
Index of refraction 2.15
Melting point 1050 °C
Thermal expansion 0.7 x 10-5/K
Crystal structure cubic
Hygroscopic NO



Luminescence properties 
Wavelength of max. emission 480 nm
Decay constant 300 ns
Afterglow <0.005% at 6 ms
Radiation length for 511 keV 1.1 cm
Photon yield at 300 K (27°C) 8-10 x 103 Ph/MeV
Integrated light output compared to NaI:Tl 15-20 % NaI:Tl