Important: Safety Warning
This page describes trade processes that use dangerously toxic materials such as cyanide solutions, mercury amalgams, or strong acids. These processes require training, equipment, and precautions far beyond what the text describes.
This information has been left in for historical purposes but should not be acted upon.
Home › Bronzing › Blackish Bronze Coloring
Blackish Bronze Coloring
For giving silvery-grey alloys a blackishbronze color, they are treated with a solution of hydrochlorate of copper diluted with a considerable quantity of water, and a small quantity of nitric acid may be added. sulphocyanide of potassium to the mixture 3820. Lead or Copper Coloring. To given in No. 3807. Or: mix 1 ounce sulphate impart a lead or copper color, add to the soof copper, 1 ounce hyposulphite of soda, 2 lution of hydrochlorate of copper, liquid am. drachms hydrochloric acid, and 1 pint water. monia and a little acetic acid. The sa monia CHEMICAL MANIPULATIONS. of copper may be dissolved in the liquid am- by a few gentle taps. The article is next heated, to dry the silicate, and the bronze be-