Based on not only the single image you originally linked, but the others that also appear in the post at Frank Updates [NSFW] as well as the photographer's own page [NSFW], it's fairly obvious there is a lot of oil of some kind on the skin of the models. The color tint of the oil used probably added a color cast as well as the other, more obvious effects (reflections, body hair stuck to skin, etc). The faces, elbows, and hands are areas that would tend to have the oil brushed away first and these areas show less of the effect than other areas. The models do appear to have spent some time in the sun tanning with certain selected areas not exposed to the Sun's rays. In addition to the oil there also appears to be some theatrical makeup applied. Use of silver tinted light modifiers also appears to have been used to give the shots the 'metallic' look. The catchlights in the head shot indicates the lighting was very directional and above and slightly left of camera.

Based on viewing other works in his portfolio [NSFW], I'd also say there is more post processing in terms of color saturation and contrast here than is typical with Ben Hassett's work.