text: Most chalconatronite formed on bronze and silver that have been treated with either sodium sesquicarbonate or sodium cyanide to prevent corrosion and bronze disease. The mineral has also been proven to form on the surface of copper artifacts after being treated with aqueous sodium carbonate. This formation by using sodium sesquicarbonate is undesirable by many antique collectors, as the mineral changes the patinas of copper artifacts. When the mineral forms, it can replace copper salts within the patina, and turn the color from a rich green to a blue-green or even black.