Wilson's disease is caused by a genetic disorder, affecting an individual's copper metabolism. A distinguishing characteristic of Wilson's disease is copper accumulation in the liver. Hematoxylin and eosin (H&E) stained tissue slides commonly do not reveal the presence of copper. Copper stains, such as rhodanine or rubeanic acid, can be used to positively identify copper in liver biopsy tissue. In most histologic techniques, there are multiple stains that will demonstrate copper. The stain used to demonstrate copper for this course was the rhodanine method. Freida Carson, author of Histotechnology: A Self-Instructional Text, has said that the rhodanine method is more sensitive, but may also be less specific than the rubeanic acid method.