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I am looking at how to create a realistic looking gold material (for instance for ingots). I found this gold material at blend swap.

enter image description here

The shader uses a mix of colours (mixing forecolor and middle color and then mixing again with a back color). Can someone explain this? Why this mixing of colors? How does this work ?

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  • $\begingroup$ @cegaton yes I did write him a Facebook message but he did not react $\endgroup$
    – user13877
    Oct 25, 2015 at 16:06
  • $\begingroup$ can you write a personal message on blender artists.org or only forum posts ? $\endgroup$
    – user13877
    Oct 25, 2015 at 16:12
  • $\begingroup$ @Elbrujodelatribu can you answer this one? $\endgroup$
    – user1853
    Oct 25, 2015 at 16:23
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    $\begingroup$ sorry, I answered to Jan before see this question here ;) I did a render about ingots with Colombia Gold material. You can see it on elbrujodelatribu.deviantart.com/art/… (you can find some info about it in its description and commets) $\endgroup$ Oct 26, 2015 at 16:14
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    $\begingroup$ Ok, I will answer this. I'm going to prepare it properly. $\endgroup$ Oct 27, 2015 at 17:16

1 Answer 1

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When I create a Cycles material I make this process:

1) I take real references. When I make a material I pretend it to be realistic, since Cycles is a physically based render engine. In this case I took these references:

enter image description here

  1. Tutankhamun mask (Egypt Gold?)
  2. Yotoco pectoral (Colombia Gold?)
  3. Some gold ingots
  4. An ancient coin

You can notice that there are many types of gold materials.

2) I try to find the correct mix of diffuse-glossy-SSS-transparent-etc shaders, making several tests. This was the second material I published in Blend Swap, so I had little experience in Cycles. So I made more than 100 tests. It is very important that you use a good test scene (Tuqueque's Blender Ball or others)

enter image description here

3) Finally I tune or adjust some details, for example colors or textures. In my first attempt I use a color picker. A color picker is a tool which catches the RGB components of a pixel in my reference image. You can use any photo edition software. I use Firefox and its Rainbow addon. Then I make more tests. Depending on my results I pick other pixels or use the blender color wheel to adjust the colors.

Here I show you the Rainbow addon catching a RGB color pointed by the mouse cursor:

enter image description here enter image description here

TIP: A real material,like gold, has many hues. You can not make it mixing only a diffuse color and a glossy color. I recommend you use several colors and use Fresnel or Facing factors to mix them properly in a physically correct way.

NOTE: I am very proud of this set of gold materials. I used the same nodes to create the copper material. I only changed the colors. It is available in Blend Swap.

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  • $\begingroup$ I really appreciate it that you want to share the concepts and ideas behind your Gold Shader !! Thanks a lot !! $\endgroup$
    – user13877
    Oct 29, 2015 at 13:40

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