Older Ral Partha figure painted in acrylics. The metallic areas are polished metal with transparent glazes for coloring and shading. See all my pictures for more views.
The way I did the metallic finish is quite simple, 1) clean and polish all the metallic surfaces, 2) mask all the metallic surfaces with Ambroid E Z Mask(several even coats),
3) primer and paint all other areas as usual, 4) remove the E Z Mask carefully, 5) glaze the exposed metallic areas with Citadel inks or thinned down paints of your favorite color (mix the inks or paints with Vallejo Matte Medium for better flow and control) for highlights and shades.