A method of manufacturing a glass article comprising: forming a first layer of a first metal on a glass substrate, the glass substrate comprising silicon dioxide and aluminum oxide; subjecting the glass substrate with the first layer of the first metal to a first thermal treatment; forming a second layer of a second metal over the first layer of the first metal; and subjecting the second layer of the second metal to a second thermal treatment, the first thermal treatment and the second thermal treatment inducing intermixing of the first metal, the second metal, and at least one of aluminum, aluminum oxide, silicon, and silicon dioxide of the glass substrate to form a metallic region comprising the first metal, the second metal, aluminum oxide, and silicon dioxide. The first metal can be silver. The second metal can be copper.