Honjo Koken hand fabricates 20,000 metal fenders each year. They’re regarded as the best bicycle fenders in the world, and are priced accordingly at $150 and up. Honjo fenders mostly made from aluminum or brass, but the Honjo rep visiting the North American Handmade Bicycle Show in Sacramento has a prototype titanium fender on display.
The rep tells me they plan to begin production of this H3 Titanium Mudguard beginning sometime in the spring. Titanium fenders would look mighty fine on just about any custom bike.