The Kayser Fleischer ring.
D004396:Coloring Agents; D003300:Copper / Q000032:analysis; D003315:Cornea / Q000032:analysis; D003886:Descemet Membrane / Q000032:analysis; D006527:Hepatolenticular Degeneration / Q000378:metabolism; D006801:Humans; D008854:Microscopy, Electron; D010858:Pigmentation
D004396:Coloring Agents; D003300:Copper