Here’s the thing: if you change the thickness of the layer then the colour will change along with it, but the material is otherwise the same. This occurs because the layers produce a phenomenon known as thin film interference. So it’s not the material of the coating layer that produces the colour, it’s the interaction between two layers.
Anyway, you can see all of the colours of a light’s spectrum through a prism but you wouldn’t say the prism itself is any of those colours. It’s transparent and refractive. That’s all we have here with the glasses: refraction and reflection, with interference of certain wavelengths due to the exact thickness of the layers.
Here’s the thing: if you change the thickness of the layer then the colour will change along with it, but the material is otherwise the same. This occurs because the layers produce a phenomenon known as thin film interference. So it’s not the material of the coating layer that produces the colour, it’s the interaction between two layers.
Anyway, you can see all of the colours of a light’s spectrum through a prism but you wouldn’t say the prism itself is any of those colours. It’s transparent and refractive. That’s all we have here with the glasses: refraction and reflection, with interference of certain wavelengths due to the exact thickness of the layers.