Factory ktm husky fork coatings

I'll wager an educated guess...   It's probably titanium nitride.
Titanium coatings can pretty much cover the entire visible color spectrum.

It's TiCN-MP. I've offered it for almost 15 years, so it's a solid coating that is plenty durable if you're looking to do that to your bike. Coating quality and color can be WILDLY different from coater to coater, so make sure you use a reputable and established shop or deal with the hassle of sending it to a shop in a different country that you trust. Sending in a test piece to make sure it comes out the copper color you want before you send in parts for your build also is a good idea.