Abstract This case illustrates the calcification of an abscess caused by partial perforation of a sigmoid diverticulum. The perforation had occurred many years ago and probably had not extended through the peritoneum. The heavy weight of the mass finally caused pressure enough to bring about unbearable aching in the lower abdomen and thighs and led to seeking medical advice. The lesion was misdiagnosed as a calcified ovarian tumor or cyst but was easily and conservatively removed. It resulted from a non-specific infection and a good recovery occurred after conservative removal.