Black dermographism is a darkly pigmented or black skin discoloration due to surface deposition of metallic particles on the skin. It occurs underneath rings, bracelets, other jewelry, and other metal objects directly in points of contact with the skin.

Gold is most commonly associated with black dermographism, but objects containing silver, platinum, copper, nickel, and iron are also frequently associated. Abrasions between these metals and makeup powders, sunscreens, and toothpastes applied to the skin – especially those containing zinc oxide or titanium oxide – can result in physical deposition of pigmented metallic particles.

Unlike true dermographism, black dermographism is not an urticarial-type reaction. Therefore, black dermographism does not appear as localized wheals and should be neither pruritic nor erythematous.

Most cases are asymptomatic, and the discoloration is not permanent.