Texturing only really consisted of a quick poly painting pass on all three figures. I didn't actually try to paint in any details or colour, but rather just tried to put emphasis on the cavities and darker areas. This was really for more of an occlusion type pass, rather than the actual details. ZBrush's Mask by Cavity option allowed me a quick way to paint most of the details I wanted. By selecting it, I could just use the Fill Object button under Colour to instantly fill all the cavities with colour.
All the lighting and rendering was done inside of ZBrush. Before this project, I really didn't have any experience with lighting in ZBrush. Though it's not as powerful or advanced as systems like V-Ray, I found that ZBrush's lighting system worked really well for simple lighting setups. The advantages of not having to export out high-res meshes or displacement maps, and how easy it is to set up the lights, can make ZBrush's lights a great choice for simple still images. Some materials in ZBrush have the lighting information built in. That is great for sculpting, but probably won't work for final images. Choosing the Basic Material will allow you to use any lighting setup you can create.
For this image, I only used three lights: one above and one at each side. By using a simple black material on a black background, I was able to render out the lights in their own pass that could be 'screened' on in compositing. Besides the lighting passes, I also rendered out a base, flat colour, and specular pass (Fig.03). Each of these was rendered over a black background and half-sized. By making the document size twice the size that you actually want, and then zooming out to half size (Zoom > AAHalf), you are able to smooth out the anti-aliased edges.
The base pass was just a simple grey material with standard lighting; this just gave me something to start compositing over. Next I added both the top and side lighting passes with the Screen blending mode in Photoshop (Fig.04).
To fake a sub-surface look, I combined several different images of marble and granite (basically anything with lots of variation) in different blending modes until I came up with my sub-dermal layer (Fig.05).