Material Editor > Maps rollout > Click a Map button. > Material/Map Browser > Speckle
Speckle is a 3D map that generates a speckled surface pattern that's useful for diffuse mapping and bump mapping to create granite-like and other patterned surfaces.
Size—Adjusts the size of the speckles. Use this to make the speckles match your geometry. Default=60.
Swap—Exchanges the two color components.
Color #1—Represents the color of the speckles.
Color #2—Represents the color of the background.
Click one of the swatches to display the Color Selector and change one of these component colors.
Maps—Click a button to assign a map that replaces one of the color components. Turning off the check box turns off the associated map (the Speckle map reverts to the associated color component).