Silver coins dating back to the Nizam era were unearthed from a dilapidated house in Nalgonda district. In all, 24 silver coins weighing about 266 grams were unearthed. Of this, 11 belong to the sixth Nizam Mir Mahabub Ali Khan and 14 to seventh Nizam Mir Osman Ali Khan. These coins would be kept with the Archaelogical Department, a release from Chief Minister’s office said on Wednesday.