metal coloring by anodic oxidation
1Anodizing — Anodizing, or anodising, is an electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts. Anodizing increases corrosion resistance and wear resistance, and provides better adhesion… …
2Spa bath — Note that the term spa bath can also refer to a spa or hot tub. A spa bath basin of water having a temperature of up to 45 degrees Celsius (#expr: 45 *9/5+32 Fahrenheit), containing salts, herbal extracts or herbal oils, in which the hands, feet… …
