Titanium can be colored using a variety of processes, including anodizing and flame coloring. Here's an overview of these processes:
Anodizing is an electrolytic process that creates a layer of oxide on the surface of the titanium. The thickness of the oxide layer can be controlled to produce a range of colors, from bronze to blue to purple. Anodizing also improves the corrosion resistance of the titanium surface.
Flame coloring involves heating the surface of the titanium to a high temperature to create a layer of oxide. The thickness of the oxide layer can be controlled by adjusting the temperature, and the resulting colors can range from golden yellow to blue to purple. Flame coloring is a simpler process than anodizing, but the resulting colors may be less durable.