I have a small stone collection from my patients in Nigeria. Stones can form in many parts of the body such as the gallbladder, kidney, bladder, appendix, tonsils, salivary glands etc. These stones can cause obstruction, pain, and infection,  so many stones need to be removed. 

The two stones in the lower left came from the distal urethra in a man. They were originally kidney stones that passed into the bladder and then into the urethra. They were too big to pass out and caused obstruction at the end of the penis,  like a ball valve. In order to urinate, the patient had to push the stones proximally! They were easily removed with a small incision.