The color can be changed using the stocked in CoronaSelect material there are a total of 14.
Who works in the V-Ray version lower than 3.1 be careful in the materials in the BRDF section there is Microfaset GTR (GGX) if your version is older than 3.1 then the BRDF field will be empty. Choose Blinn Phong or Ward – which is preferable for you.
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