Majolica with Mayco Stroke & Coat Colors; Mixing Your Own Colors

Someone asked recently about what I’m using for majolica decorating, now that the AMACO GDC colors are discontinued.

Thanks to Susan Hunter at C & R Ceramics in Ocala, FL, I was able to test Mayco Stroke & Coat colors on top of my majolica base, fired to cone 03 sitter cone/ small 04 cone visual at about 200 degrees/hour. See the Mayco link for their product information. The colors were originally intended as cone 06 glazes, and can be used to decorate on top of a viscous white glaze for majolica inglaze decoration. The series offers a huge number of color shades, and whoever named them had a good time making up fun color names. The work well, and have been successful for making smooth ground color – they brush smoothly, and don’t move when fired. They are, however, like putting a glaze on top of the majolica glaze, and any texture in the base glaze tends to pick up. There are some light distortions at the top of the images below as I just popped the tiles down on my scanner to try getting an image. Setting up my photo lights and screens would have made better images, but would not have happened as soon.

Mayco Stroke and Coat tile 1 PP

Mayco Stroke and Coat tile 2 PP Mayco Stroke and Coat tile 3 PP The commercial colors are uniform, brush easily, and are repeatable. In spite of that, I am liking my return to mixing my own colors. The gum component in commercial colors, if over-done, can make the colors gloppy for brushing fine lines. Manufacturers may change colors or formulas without notice. The use of a color that is glaze-like over the majolica makes a more translucent color for some colors. Whether this is an asset or a liability is a matter of personal aesthetic.

I have previously posted information about Spectrum’s product, which seemed better suited to 06 firing than my 03 sitter cone firing, and A.R.T.’s Glazewerks Maiolica colors, which worked well at my temperature and with my glaze. If you’re looking for my glaze recipe, see the Majolica and Lowfire handout on my website handouts page.

I’m preferring the control, flow, and look of mixing my own colors, and have bought some low, wide-mouthed jars for my colors (so I don’t knock them over on my table). Details on what to mix below. Bentonite bloats in water (like adding cocoa or cinnamon to liquids) and will lump up unless mixed with the dry ingredients first (like mixing your cocoa with sugar first). I stir dry (don’t breathe the dust!), add water, and mix with a small wisk. I generally then screen in a small test sieve. Talisman and Euclid’s offer such screens. I’m using an 80 mesh, and push the mix through with a mini silicone spatula.

Most of what I’m using are stains, mixed with frit 3124 and bentonite by volume (e.g. by teaspoon) at a proportion of 1 color + 1 bentonite + 3-4 frit. I tried using less bentonite – 1/2 – , thinking less clay would give me a cleaner fine line with black, but it tended to smear when waxed over. I’ve gone back to using equal amounts stain and bentonite. Most stains are good with 3 parts frit to help melt them into the glaze surface. There are exceptions, though. Many of the blue stains are refractory (resistant to melting) and need 4 parts frit to help them melt in. the mineral rutile (orange-brown fired color) and chrome oxide (opaque grass green color) work well as colorants, but are also refractory and need 4 parts frit. Copper carbonate, cobalt carbonate, manganese dioxide, and iron melt at lowfire temperatures, and would be mixed at 1:1:1 proportions. I do use copper to modify some green and blue colors. Putting it on very heavily will cause a silvery surface that will probably leach with acid foods. If you get that result, you’re using it too heavily for food use. Cobalt carbonate works well, but is pale lavender-grey raw. This makes if hard to remember what is where while working, and hard to visualize what may be a navy blue result. This could be avoided by putting blue food color in your cobalt-frit-bentonite mix. Since iron is just brown and manganese is brownish, I rarely use them for majolica, although they can work. Manganese gives off toxic fumes in firing. As a decorating color for majolica, this would be a small amount, but still toxic.

Stains designated as body stains (for coloring clay bodies at all temperatures) are too refractory for majolica use, and even when mixed with flux give a matte pig-skinned (wrinkled) surface on top of most majolica glazes. Some of those stains: Mason 6020 Manganese-alumina pink, 6485 Titanium yellow, 6319 Lavender.

For those who remember the original AMACO GDC Light Red color, which was a lovely red-orange toward persimmon, Mason Lobster stain is that color and can be mixed as above.

Happy decorating.

A.R.T. Glazewerks Maiolica colors

Thanks to the nice people at A.R.T. Studio Clay Company, I have just tested their Glazwerks Maiolica colors on top of my standard white majolica base (listed in the Majolica and Lowfire handout here.) The tile was fired at 200 deg/hr to a cone 04 visual at about 3 o’clock (about 1950 deg F at this ramp). If you have a kiln sitter, that would be an 03 sitter cone. Right side is a double coat. The results look good – a workable substitute for the discontinued AMACO GDC colors. Yay! See the tile below. I tested 10 of the colors. The remaining test were mixes of colors. Product is listed in their catalog on page 12:

ART Glazwerks Maiolica colors on Arbuckle majolica, 04 visual cone

ART Glazwerks Maiolica colors on Arbuckle majolica, 04 visual cone

More Majolica Decorating Color chat

David Gamble, lowfire clay artist, Skutt kiln expert, did an article a while back. I don’t remember where – someone out there remember? Tell us! – about the various products for decorating on majolica glaze. I asked David to recap his experiences for us. He said:

When I did all my tests I found GDC’s seemed the best – Spectrum was 2nd in my use & assessment and they had lots of color – I heard Color Robbia had some but folks I know said they did not like them & I never tested them – Mayco says that their Stroke & Coats work & yes they melt on top of whites – but I found that they were not as stiff & moved/bleed at the edges – so exact lines were out of the question with them.

 All your tests with velvets on white glazes are still good with me — though not sure about food surfaces – they are so soft they would have to melt completely into the surface to be dinnerware safe. Of course you already know all of this.

Before there were GDCs, I tested the AMACO Velvet Underglazes on top of majolica. The results of this are posted on my website Handouts page. Some melted very well and were usable for majolica, some were very refractory and pig-skinned (so matt they left a crinkled, stony surface on top of majolica.)

David was in touch with AMACO, and checked on the availability of GDC colors at this point. He reported:
They are out of pink in 2oz but have pints of pink left — red & turquoise are low in pints around 10 each .  Seems to be lots of 2 oz jars left in all except pink colors.

So folks should get them know while they still have a great selection at AMACO’s retail store – Brickyard Pottery- Cheri is the manager you can call 317 244 5230  or Amaco’s 800 – 374 1600  and ask for Cheri at BYP .

In my studio world, pink is safe, and so is brown. I probably have enough brown for the rest of my studio lifetime. I’d probably run out of the bright yellow (mixed with turquoise 3-4:1 it’s a great Chartreuse), Light Red, Pearl Grey, and Avocado first.  At one point, I did make it a project to use brown, just to see if I could. I do like certain browns – nice ochre-tan-saddle colors, and reddish, rusty browns. Below, a bowl from 2003 during the self-imposed brown challenge. Summer flowers on the front, winter leaves on the back. Perhaps the theme presaged my later immersion in George R.R. Martin’s Game of Thrones series and the house of Stark motto: winter is coming.

Arbuckle majolica bowl, 2003, Now and Then

AMACO GDC Majolica Colors Sail into the Sunset

AMACO has announced that it’s GDC line of color for majolica decoration will be discontinued in December. It may be available through specific suppliers through the following year, but production will cease. These have been my go-to colors, supplemented here and there, for a number of years, so I’m sad to see them go. It was not a profitable line for AMACO – we use these in small amounts and there were 36 colors. There was at one point discussion about making fewer, more inter-mixable colors, but the final decision was that they were focusing elsewhere in the product line. My thanks to AMACO and its good people for the conversation and support over the years I’ve used the GDCs. I’ve appreciated the product line and my relationship with the company’s people.

Before the GDCs, I mixed my own colors. This began with Gerstley borate as a flux, mixed with oxides or stains. The GB kept things in suspension, made brushing easy, and gave a firm surface when dry to wax over. BUT, the GB gave a very tiny reticulation of miniscule white snowflakes in melting that pastelled the colors. Even before the announcements of the GB mine closing, I was aware that people using frit for a flux had brighter, denser color on majolica. Switching to frit + color or stain revealed that this mix alone was very powdery when dry, and made a real mess if handled, or waxed over – smearing, smudging. Pete Pinnell, the Mister Rogers of clay and glaze materials, advised adding a bit of bentonite, and that did take care of the problems. The colors brushed better and were firm enough to wax over when dry. I’ve been experimenting with adding glycerin or CMC gum for added brushability, but too much of that makes the mix gloppy and interferes with crisp line quality. Still looking for the sweet spot. the mixes I was using:

  • Oxides that melt well at low fire (copper, cobalt, manganese, iron) are mixed by volume (say, teaspoons) 1 colorant + 1 frit (I used 3124 because it’s in the glaze I use) = 1/2 bentonite.
  • More refractory (resistant to melting) oxides (chrome, rutile, nickel) or stains are mixed by volume 1 part colorant + 3-4 parts frit + 1/2 bentonite.

Bentonite “bloats” in water – like trying to mix cinnamon or cocoa powder with liquids – so mix dry with other materials and then add water. Screen if lumpy. There are some nice, small test sieves that fit in a pint container available at the ceramic suppliers.

I have some tests in mind with varying the bentonite and CMC, and trying Veegum-Cer, which the commercial people use in their colors. The last iteration of the GDCs seemed over-gummed and a bit gloppy for good line quality to me, so it’s a needed push out of the nest to do my own testing.

There are other commercial products. I was just given a sample of Spectrum Majolica colors. I fire to 03, and at 03, some of the colors are broken and seem over-fluxed. See image below. The top 3 rows are the Spectrum colors, the last block to the right in row 3 is a test of chrome chloride and water (a soluble colorant toxic raw), and the bottom row is mixes of the Spectrum colors I was curious about, as I had open squares on my test tile.

Mayco has product for this as well. More later on this. My testing life is s-l-o-w as we are in the busy last part of the semester at school, and I’m also being treated with i.v. antibiotics for Lyme disease. I hope people who have experience with other products will comment.

Test of Spectrum Majolica colors on Arbuckle majolica glaze

Test of Spectrum Majolica colors on Arbuckle majolica glaze. Fired to junior cone 04 at 3 o’clock in a visual cone.