Can urine be bloody after passing a stone?

Yes: During the time of and shortly after passing a urinary stone, blood is commonly found in the urine. The stone is an accumulation of crystals/salts that are sharp on the edges and cause minor tears/cuts tp the inner lining of the urinary system/tubes (such as the urethra). The lining generally reproduces quickly and so it recovers quickly if the tearing of the surface is minor.