I shamelessly lifted this text from Diana Pancioli's Website
. You may want to visit her
site for the graphic that might make this method clearer. It looks
to be a highly effective method for investigating small percentage,
one ingredient modifications to a given glaze. Good luck, and
please report back how this method has worked out for you.
FAST FIVE TESTING
This testing strategy for ceramic glazes is fast and effective. It
can be used to test colorants—to explore increasing amounts of
saturation—or to test base glaze additions in order to explore
changes to a glaze or to correct problems. I didn't invent this
technique; it was used by chemists in an earlier age to investigate
materials without weighing out tiny amounts. The "Fast Five" is
accurate enough to point to possible solutions with very little
investment in time.
- Weigh out 10 grams of a colorant or additive. Square and
flatten the powder onto a piece of paper with a knife or
- The Plan: With your knife, you will divide the 10 gram square
in half and push the half to one side. Then you will divide one of
the halves in half again, push it aside into a separate pile and
repeat this four times, until you have 5 piles of the
- Push each pile aside as you divide it.
- Beginning with the smallest pile, add it to 200 grams (100 dry)
of a wet base glaze. Just assume that 200 wet grams equals 100
dry—it is close enough.
- Stir the addition into the glaze and apply it to one end of a
rectangular test tile (about 2 x 5 inches).
- Continue to add the dry ingredient into the same cup of glaze,
the smallest amount remaining each time. Remember to apply the
glaze to the tile after each addition.
- Label the back of the tile withglaze name and additive. You
need not write the amounts on the tile as the percentages are
always the same in a Fast Five test.