Mammographic detection and characterization of breast microcalcifications is important in the early diagnosis of ductal carcinoma in situ. A case is presented where tungsten microparticles simulated microcalcifications and prompted a full diagnostic assessment. The likely origin of the particles is discussed and the published work on metallic particles in the breast is reviewed. Awareness of possible alternative causes for apparent microcalcifications at mammography is important for the breast radiologist and pathologist.