gold ruby glass?
what acids do i mix togeather to melt desolve gold in to make aqua regia and in what percentages to add to my glass batch to make a rich ruby colour
- 1 decade agoFavorite Answer
For a ruby red glass you need to do what is referred to as "Striking of a ruby" or "Striking the glass". 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.
This porcess 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.
As for the acid digestion of gold, unless this is for a university project that requires such a process it is not the best way to go. If you have to use acids, you can digest gold with H2SO4 but use an aggitated bath close to 90C (also it will take about 48 hours).