Legor's RU5BLACK-X is an extra black ruthenium plating electrolyte which deposits a glossy layer of ruthenium metal in a jet black color. The solution is sold as a kit with the ruthenium solution as part A and the blackening agent in powder form separately as part B. The black color produced is developed with additions of heavy organic additives that oxidize the ruthenium metal as it is deposited. Precise mixing instructions must be followed to obtain optimum results. This acidic based compound is primarily used in decorative plating applications for a deep black color option in the case where corrosion resistance is also a requirement. Due to the fact ruthenium has a lower conductivity than other precious metals, the electrolyte requires a greater metal concentration to function optimally. The formulation is 100% arsenic free both in the metal deposited and in the chemical itself and falls within REACH compliance. 1 liter bottle. MSDS. Technical Sheet.