A very rare case: An 80-year old woman presented with acute T.IA. (Transinet Stroke). Brain MRI, documented embolic infarct. Electrocardiogram showed normal rhythm, without arrhythmia and ultrasound of carotids was normal. No history of any other underlying disease. Echocardiography, Transthoracic and Transoesophageal, showed, a HIGHLY MOBILE MASS, (1.5/1.0 cm), attached to the posterior leaflet of Mitral valve. This mass could be a benign tumor, such as myxoma or fibroelastoma or something else! Not typical for any common findings. It was clear, that this fragile mass, was the reason of brain embolization. The patient underwent urgent Cardiac operation (coronary angiography just before, showed clear coronaries as well). During operation, under Transoesophageal guidance, the mass was successfully removed carefully, with repairing of posterior valve leaflet. The patient recovered easily. Histology examination showed that this tumor was CASEOUS CALCIFICATION. This is very rare entity which is even rarest cause of Stroke. Early removal prevents further episodes. (Cardiac Care Centre, Paphos and YGIA POLICLINIC, Limassol).