Chondro-osseous calcific vasculopathy of the medial layer of an atherosclerotic human artery. Histological section (hematoxylin and eosin stain; original magnification X100; provided by Qiao, J.H., Mertens, R. B., Fishbein, M.C. & Geller S.A. Cartilagenous metaplasia in calcified diabetic peripheral vascular disease: morphologic evidence of endochondral ossification. Hum. Pathol. 34(4), 402–407© 2003, with permission from Elsevier).