The object is lit by a highlight and by the reflection of the surrounding (from a cube map). Both highlight and reflection take into account the material color of the object to generate a realistic metal effect.
Note: This plug-in is located in: Built Ins -> Shader -> RTTAdvancedMaterials
Metal Reflection Shader Properties
Environment Reflectivity: Manipulates the influence of the reflection color from the environment map on the resulting color.
Reflection Multiplier/Exposure: Affects the exposure of the environment map. This is especially helpful when working with HDR images.
Gamma of EnvMaps: Controls the gamma correction of the environment map. This is once again particularly helpful when working with HDR images.
Environment Map: Is a cube map that describes the environmental surrounding used to calculate reflections.
Metal Reflection Shader Best Practices
Apart from the parameters in the plug-in container, it is necessary to assign a material and a texture as a color/basic texture. Do not forget to adjust material parameters in addition, such as ambient, diffuse, specular color and shininess, to achieve the required look for your surface. To achieve a photo realistic, metallic look, it is recommended to assign any color but white as a specular color.