On Reddit, I would bang on about under-coating numbers on clear or translucent dice to prevent “color bleed”. This set was designed to use the effect in a positive way.

I cast a clear set of dice and first painted the numbers in ROYGBIV, starting with the d4. I then painter over all the colors with gold. I have polished the set to a matte finish to increase the effect.

Here is a close-up on the d6 to better show what’s going on. clear, matte finish d6 with gold numbers but orange underneath the gold.

This will still darken a clear die, even if you use a bright silver or white, as it stops light from coming through those areas. I do find it preferable to color bleed, however.