How to make a metallic effect just in Yellow pixels from image texture (Texture Sample) with Base color, normal map and specular texture ?

Hello, Do you know how to make a metallic effect on yellow pixels from the image texture like in Dark Deception or Resident Evil village with a texture mixing marble and gold.

Let me explain, I want to create a metallic effect on the yellow pixels of a texture image but which does not metallicize the pixels of another color, for example, I have a texture where there is marble in gray, and orange-yellow gold.

I only want to create the metallic effect on the yellow pixels, without affecting the gray pixels with 3 sample textures, the Base Color, the normal map, and the specular textures, without having to create a mask texture on photoshop or gimp.

How can I do this?

so you basically want to mask by color…like a chroma key…