Here's my personal X-O buckle:
There is a lot of detail you can't see in most photos and there's more aging on the feather than just the extra "yellowing" from the X-1 verison. This one took me a lot longer than I care to admit, but I wanted to get all the detail just right.
The yellow was pre-mixed to the shade I wanted and then I did various black washes (black acrylic with water) to get the different shading effects I wanted. All the silver was brought back using a small screwdriver to carefully scrape the paint off exactly where I wanted. Then the entire piece was coated in a polyacrylic spray to prevent further scratching.
Kind regards,
Magnoli