The type locality for Miargyrite is Bräunsdorf, Freiberg District, Erzgebirge, Saxony, Germany, where small but lustrous crystals have been found with Quartz. A classic European region for this mineral is Baia Sprie and Baia Mare (the Herja Mine), in Maramureș Co., Romania.
Perhaps the finest specimens of Miargyrite have come from the San Genaro Mine in Huancavelica Department, Peru, where it forms in relatively large examples for this species including thick crystal masses. In the U.S., crystallized examples as well as silvery masses come from the Kelly Mine, Randsburg, Kern Co., California.