Disclosed is a crystal 1 of thallium arsenic selenide, thallium arsenic sulfide, thallium vanadium sulfide, thallium phosphorous selenide, lead halide, cadmium sulfide, cadmium selenide, cadmium tin arsenide, cadmium germanium arsenide, indium phosphoride, indium arsenide, or mixtures thereof, doped with a precious metal in an amount of about 25 ppm up to the solubility limit of a precious metal in the crystal. The crystal is useful in nonlinear optical devices, acousto-optical devices, piezoelectric devices, and other types of optical and acoustic devices.