Scanning electron micrograph of crystals of calcium phosphate on the surface of tibial (lower leg bone) cartilage in the knee joint of a patient with chondrocalcinosis. The disease is characterised by the presence of calcium phosphate crystals in joint cartilage, which cause inflammation, swelling, reduced articulation & may lead to the destruction of the joint. The disease is also known as pseudogout for its resemblance to gout. The crystals associated with gout, however, are formed from sodium urate due to a malfunctioning of the uric acid metabolism. Magnification X1,500 (at 13x13cm size).