TREATMENT OF A SILVER DRAGON FOR THE REMOVAL OF SILVER CYANIDE AND CHALCONATRONITE
Donna K. Strahan
2 DESCRIPTION AND EXAMINATION OF THE SILVER DRAGON
THE MEIJI PERIOD (late 19th century) dragon was made of silver with the remains of gilding on its claws and tongue. X-radiography of the dragon showed it was cast in five separate sections and was soldered together to form its serpent-like shape. Composition of the surface metal was determined by x-ray fluorescence to be 6% copper and 94% silver, a composition similar to sterling silver.3 A coating over the object's surface was identified by infrared spectrophotometric analysis to be an acrylic resin.
The blue and the gray corrosion products were found scattered over the body with the main conglomerations at the intersection of the spikes on the back and along the legs. Both corrosion products occurred in close proximity, and there was less blue corrosion than gray corrosion. The blue corrosion was generally fluffy; however, in some areas it was compact and appeared visibly crystalline.
Both corrosion products proved to be light sensitive. The blue corrosion color faded after two months exposure to the laboratory environment. After roughly a month in the laboratory, the gray corrosion had converted to a charcoal black color.