Mayco Yellows at Cone 10

Written By William Shepherd

I like to work with Mayco’s Stroke and Coat line, since they’re stable and (usually) true to advertised color at cone 10. There are some exceptions though, notably yellows and purples, where they tend to burn away at such high temperatures.

Peep this color wheel I created to test out different combinations of Mayco glazes, specifically the combinations with Mayco’s Sunkissed:

  1. 75% Sunkissed, 25% Cotton Tail

  2. 100% Sunkissed

  3. 75% Sunkissed, 25% Gray Hare

  4. 75% Sunkissed, 25% Tuxedo

We can see how the yellows have burned out, leaving a pale greenish color.

However, the pottery community hasn’t let me down. I heard through the pottery grapevine that you can mix a little bit of underglaze to add back in some pigment that burns off.

I tested this very un-scientifically by mixing an unknown amount of Coyote Yellow-Orange underglaze with Mayco Sunkissed, and got literally the PERFECT yellows with the following sunflower designs.

This was such an improvement over the previous yellow tests I’ve done. But naturally, I started running low on this perfect concoction I had whipped up, so it came time to recreate. But when I tried adding more of the Coyote Yellow-Orange + Mayco Sunkissed combo, you can tell I didn’t maintain whatever golden proportion I happened to land on for the first time:

The sunflowers in the Sunflower Field plate (far left) are darker than that first yellow I landed (far right). It’s slight, but it’s noticeable.

To get to the bottom of the problem, I designed an experiment to see how various levels of yellow underglaze and glazes can survive at cone 10.

Experiment: Combining 2ml of three different Coyote Underglazes with varying proportions of Mayco’s Sunkissed:

  1. 2ml of [Underglaze] + 2ml of Mayco Sunkissed

  2. 2ml of [Underglaze] + 4ml of Mayco Sunkissed

  3. 2ml of [Underglaze] + 6ml of Mayco Sunkissed

  4. 2ml of [Underglaze] + 8ml of Mayco Sunkissed

The three Coyote Underglazes I tested were:

  • Buttercup

  • Yellow

  • Yellow-Orange

And the results were interesting! However, I’m currently in Hawai’i writing this post and will post the results as soon as I can take a picture of them, stay tuned!

William Shepherd