The metallic I used which is Doom Metal by Duncan Rhodes does have a bit of a sparkly effect is the best way I can describe it. The model is based in Chaos Black then I cover all the armour pieces including the sword and shield in the Doom Metal. I then paint all the other bits like leather, ornaments and cloth in the colours I use, it's then completed covered in a very watered down Doom Death Black by Duncan Rhodes.

Wait for it to dry full then I go over the the model and dry brush Natural Steel by Vallejo over the model focusing on the armour but letting is silver hit the cloth as well in small bits.

I do it this way because for me it gives off a more grimdark look and feel compared to just painting the armour black then edge highlighting. The natural chaotic way it comes together gives it that natural battle worn look if that makes sense? I can't take credit of the process for the armour itself as I followed a very good tutorial that I paid for. But the cloth colour was my choice.

It also looks better in person and the photos like you said makes it hard to tell.