Why does gold turn glass red?

Question

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I appreciate all answers here. Thank you.

Specifically, from a physics viewpoint however, I am interested in how the electromagnetic frequency of Red light is affected by the joining of Gold and Quartz, or Gold and Silicon or any other type of Glass. I think Red Base and Gold Chloride Color are closely linked to this answer :)

Answer 1

This is due to an effect called striking the glass.

This process occurs as a result of plasma resonance from free electrons in the colloidal metal particals. These are the gold particles of about 200 Angstroms in size. The color is a result of absorption at 0.53 micrometers wavelength.

Here's how to do it:

Add 0.01%-0.02% (wt %) Au to the batch along with small quantities of some reducing agent such as SnO2 or ZnO. Allow the glass to cool normally and don't be suprised, there will be no color. Here's the trick - after it cools heat it again to slightly above the glass transition temperature (in essence anneal the glass) and it will change to a ruby red color.

Answer 2

One of the base colors of the color "gold" is red. In fact, when painting with the color 'gold', it's a good idea to put down a base coat of red. This makes the gold so much more metalic and deep in color.

Answer 3

they use gold chloride to change the colour of the glass. this is a reddish colour but its the amount of this substance that they use that will determine how red the glass will turn out (more gold chloride=a deeper red)