An alloy of gold and copper (about four parts to one, with some accidental silver naturally in the gold) made and used by the Indians of the Andes, Central America, and Mexico for many articles of pre-Colombian jewelry. It had a lower melting point and a greater hardness than either of the metals alone. It had a dull colour but was brightened, usually in limited areas to make a design, by use of heat and a mineral paste or a preparation of plant juices which removed the copper from the surface, and was sometimes further brightened by burnishing.
Local terms for the metal were 'guanín gold', 'caricoli', and 'Karakoli'.
From: An Illustrated Dictionary of Jewelry, autor: Harold Newman, publishers: Thames and Hudson