Well , it's pretty simple . It was done using Photoshop's bevel and emboss layer style , set to down instead of up then I used a hard edged brush to paint the cracks with the layer set on multiply . The texture only uses Two colors , a dark grey as the base and a lighter grey to make the textured part with a brush set to screen so that I could get a lot of variation . The brushes are just Photoshop 7 brush presets with some adjustments to the scatter and spacing .