Milk of calcium: a structural study.

Milk of calcium is an unusual radiologic entity which covers a wide variety of stones of various compositions. They only have in common the fact that in vivo stone movement is indicated by radiologic pictures taken at different postures of the patient. Despite over 100 cases reported in the literature, no comprehensive structural and chemical analyses have been published. In our case the milk of calcium stones were found to be composed of large crystals of calcium oxalate mono and dihydrates on which clusters of small apatite needles were deposited.