The missing ingredient I left out is water - with 100 grams of course easily measured out as 100 ml. We use clear squeeze bottles from a restaurant supply store.
This is the actual mixing procedure.
475 $4.43 100.0% Color Bottles - per bottle
100 $0.00 22.2% Water
50 $4.17 11.1% Mason Stain ($8.48 to $37.50) $4.17 average cost per bottle
Pour above into bottle and shake
100 $0.17 22.2% Gerstley Borate
200 $0.00 44.4% Water
25 $0.09 5.6% Zircopax (not for Black, Grey or Taupe - but this caution has been ignored and no one noticed a difference)
Mix and sieve the gerstley borate base and add to each color bottle after the stain is mixed with water in the bottle.
Pour in the gerstley borate mixture leaving 1" at the top of each bottle then shake thoroughly.
If you mix these color concentrates with clear or white glaze in a ratio of 1 to 3, or 1 to 7, you'll quickly see that blues and greens have greater tinting power than than red and yellows. Rather than complicate matters with a different amount of each color its respective bottle, people just get a feeling for how much to add by looking at the 1:3 and the 1:7 tiles.
By itself this color concentrate is slightly more fluxed than under-glaze at ^06 and not quite as fluxed as most glazes at ^6. Gerstley borate provides needed flux and suspension in water which gives people an easy way to portion out color.
thanks for the useful information on mixing this stuff. However, I'm a little confused about your metrics. "22% gerstley borate, mixed and sieved. To this we add 11.1% mason stain plus 5.6% zircopax " Do I use these numbers as relative proportions of these ingredients?