This might be the case Cpt. Nemo would put his CDs in - with the view out of the submarine window and into the ocean .-)
With my first two cd-cases I follow in the footsteps of the master of "make metal out of cardboard": diarment. I bow to his style and try to copy (and modify) it for my own enjoyment
you paint it with a darker color - black, that is what i use - and then take a brush with only very little silver/gold/copper/bronze and brush over the cardboard very lightly. the method is called drybrushing - so take care that the brush is really quite dry, it will not work if you use too much of the metal-paint. better paint it several times until you have the "shine" you want
Captn Nemo ftw!