A circumscribed grey or brown macule resulting from chronic exposure to the sun or to artificial sources of ultraviolet such as sun-beds. They are typically located on the backs of the hands and forearms, shoulders, forehead and the scalp (if bald). They often coexist with and may be difficult to differentiate from plane seborrhoeic keratoses, which differ clinically in exhibiting fine scaling and histologically in showing proliferation of keratinocytes as well as melanocytes.