Cadmium tungstate (CdWO4 or CWO), the cadmium salt of tungstic acid, is a dense, chemically inert solid which is used as a scintillation crystal to detect gamma rays.

The crystal is transparent and emits light when it is hit by gamma rays and x-rays, making it useful as a detector of ionizing radiation.

Combining the scintillator crystal with externally applied piece of boron carbide allows[citation needed] construction of compact detectors of gamma rays and neutron radiation.

[3][4] Very high radiopurity allows use of this scintillator as a detector of rare nuclear processes (double beta decay, other rare alpha and beta decays) in low-background applications.

[6] Due to different time of light emission for different types of ionizing particles, the alpha-beta discrimination technique has been developed for CWO scintillators.