This guy is a standout sculpt amongst the metal Sternguard Veterans!
These guys appear in the 2009 Citadel catalogue under Elites.
Undercoat: Vallejo Mecha Black
Base coat: Scale75 Artist Cobalt Blue, shaded with Prussian Blue
Flex joins: Scale75 Art Black, highlighted by Pastel Blue, washed with Nuln Oil Gloss
Gold: Scale75 Necro Gold followed by a thin coat of Inktense Chestnut, then a recess shade of Inktense Chestnut. Highlights of Elven Gold, Peridot Alchemy and Citrine Alchemy
Silver: Scale75 Black Metal, shade of Prussian Blue, highlights of Cobalt Alchemy and White Alchemy
White: Scale75 Art White, highlights of Inktense White, shade of thinned Cobalt Blue
Red: Base coat of Scale75 Art White, followed by Primary Red/Red Ochre 60:40, followed by Primary Red, shaded with Dark Violet, highlighted with Primary Red, selective highlight of FX Fluor Red Ecstasy
Green for fist: Scale75 Artist Spring Green, highlight with a 50:50 mix of Spring Green and Primary Yellow
Eye lens: Scale75 White followed by Spring Green, highlight of 50:50 Spring Green and Primary Yellow, shade with Sap Green, further shade with Green Grey, highlight with White
Leather: Burnt Sienna Umber, highlighted with… I didn’t write it down. One of the parchment colours
Bone colour/Purity seals: Buff, shaded by 50:50 Buff/Burnt Sienna Umber, highlighted with Off White, highlighted with Vanilla White, text diluted Burnt Sienna Umber
Here he is mostly done: