GAGG scintillation detector with SiPM readout. Crystal size 10*10*30 mm , Nice resolution of 6.4%@662 keV measured using Atom Nano Pro electronics ans Cs137 source from the side opposite to SiPM.
For best results use with 40.5 Volts bias. Excellent gain - at least 2 nC of charge per MeV of dissipated energy with 40.5 V bias voltage.

General scintillator properties:
ParameterUnitValue
Max. Emission Wavelengthnm520
Average Light Decay Timens100-150
Average Light Yieldphotons/MeV60000
Densityg/cm36.63
Effective atomic numberZ54.4
Crystal sizemm / cm310*10*30
Energy rangekeV10-3000 min.

Want to build a portable and very sensitive gamma spectrometer - it's your chance!
Check out my other lots, I hope you will find something interesting!
Any questions? Feel free to contact me.