Creating Natural Materials in Cycles - Blender Cycles Materials and Textures - page 120

29. Connect the Bump node output to the Normal input socket of the Glossy BSDF node.
30. Add a Layer Weight node (press Shift + A and navigate to Input | Layer
Weight), connect the Fresnel output to the Fac input socket of the Mix Shader03
node, and set the Blend value to 0.300 .
31. Parent these recently added nodes to a new Frame and label it COLOR .
The COLOR frame
32. Add one more Noise Texture node (press Shift + A and navigate to Texture | Noise
Texture) and a new ColorRamp node (press Shift + A and navigate to Converter |
ColorRamp). Connect the Mapping node output to the Noise Texture node's Vector
input (label it Noise Texture03 ) and the Fac output of Noise Texture to the Fac
input of the ColorRamp node (label it ColorRamp03 ).
33. For the last time, add a MixRGB node and set the Blend Type to Difference. Then
connect the Color output of the ColorRamp03 node to the Color1 input socket of the
Difference node, and the Color output of the Difference node to the Fac input socket
of the Mix Shader01 node. Set the Fac value of the Difference node to 0.255 .