Bladder stones. Ultrasound scan of the bladder of a 58 year old male showing bladder stones (bright white). Bladder stones (cystoliths) are solid accumulations of dissolved urinary minerals that have come out of solution and built up into hard stone-like objects. They typically leave the body without any symptoms when passing urine. However, if they grow to a sufficient size they may cause an obstruction in the urethra, leading to severe pain.