Weird, Wonderful Steel Blue Opal | Bullseye Glass Co. | Bullseye Glass Co

Weird, Wonderful Steel Blue Opal

A couple weeks ago I was perusing the shelves at the Bullseye Resource Center Santa Fe, when a sheet of blue glass caught my eye. Its rich, deep teal pulled me right in; I could dive into this piece of glass and take a swim. “Steel Blue Opalescent” read the label, and I recalled that name from one of the workshops I had taken.

We were experimenting with various textures of glass frit, to see how they changed after firing. Steel Blue Opal was the star of the show. Unlike any other of the glass we worked with, this frit would fire out to be either teal blue or metallic silver, depending on the firing temperature and whether the frit was exposed to air or covered by other material. How could this be?

According to Bullseye’s product information sheet, when fired between 1250-1400 degrees F, the surface of Steel Blue Opal (a.k.a., 000146) will oxidize, creating the metallic effect. But if you take the same piece up to a full-fuse temperature (around 1500 F), the steely coating disappears and the glass becomes blue again! The folks at Bullseye almost discontinued this fabulous freak of nature when its odd behavior was discovered. Fortunately, artists enjoyed the unique properties of this glass, and persuaded them to keep it in production.

I decided to try my hand at manipulating the qualities of Steel Blue Opal to make a unique design. I cut a 3 mm panel measuring 9″ x 12″ and fused it to a sheet of 3 mm Clear Tekta. As expected, the panel came out of the kiln the same lovely teal blue color that first seduced me in the store. Now for the fun part.

Over the past few months I have been editing a manuscript about the Hopi-Tewa artist Nampeyo, who produced pottery from the late 1800s until around 1942. Incredibly talented and prolific, many believe that her work represents the height of Native American pottery made during that time. Nampeyo’s pottery is in collections from the Smithsonian to Harvard. Her designs had crept into my heart, and I was fascinated by the way her pottery looked both elegantly simple and extremely sophisticated all at once. I decided to take inspiration from the Hopi Rain Bird, a motif that appeared on many of Nampeyo’s pieces.

Rain Bird design in clear powder. The bowl I used as inspiration is on the left.

The spiral as a basic design element has always attracted me, and the Rain Bird is based on the spiral, which also alludes to the curved beak of a bird. I had a small piece of Hopi pottery that featured the Rain Bird, and I used it, along with several other Rain Bird images by Nampeyo, to create my own interpretation of the iconic design. I decided to use clear frit as a masking material, so that I could uncover areas of the surface that I wanted to appear silver, while keeping the blue in areas where I left the layer of frit.

Back to that idea of how a seemingly simple design becomes incredibly complex once you really look at it: my experience of making the Rain Bird design was very enlightening. I sifted a thin layer of clear powder over the top of the entire panel, then took a thin stylus and began tracing the swooping spiral of the central shape. After getting a basic outline for the form, I went back in with a small paintbrush and oh-so-carefully removed powder from the spots that I wanted ultimately to be metallic. This was an incredibly tedious process, made more intense by the fact that there would be no opportunity for erasing or “do overs.” Once the powder was disturbed, I was committed. It was a good thing that I was wearing my respirator, as it prevented stray puffs of my breath from disturbing the frit powder. Regardless of this, I found myself holding my breath as I drew tracks through the frit and then brushed away the residue.

By some miracle, I managed to get the design the way I wanted it on the first go. It was almost as if I had drawn the motif before, which probably came from the fact that I had studied the design on so many pieces of Nampeyo’s pottery. Whether or not I could ever replicate the feat is unclear. Nampeyo often made multiple versions of every piece she designed, to compensate for the large number of pots that failed during firing (cooking your pots in a pit dug into the ground—and using animal dung to fire them—is a far cry from our modern electric, digitally-programmable kilns). My modest attempt to create a Rain Bird design left me with a whole new level of respect for Native American potters.

The finished Rain Bird panel.

Once the design was done, I immediately placed the glass into my kiln—God forbid my pet cockatiel Chirpy should decide to take a stroll across the powder-covered panel before I got it fired. I programmed the firing to a peak temperature of 1400 degrees F (with a hold of 10 minutes) and went to bed. The next morning I cracked the kiln to see a metallic silver Rain Bird swooping across a field of intense blue. I was thrilled!

After a few days, I decided to add some texture to the surface, to emphasize the slick shine of the central design. Using clear powder frit, I again dusted the entire surface of the panel, removing the material where I wanted the original shiny surface, and leaving it where I wanted to have a sugary matte texture. Back into the kiln it went, this time only firing to a peak temperature of 1275 degrees F to tack-fuse the powder without completely melting it.

The finished panel is an interesting blend of shiny and frosted surfaces; the edges of the glass are the same metallic silver of the central design, as the edges were not coated by clear frit. I’m very happy with the result. I haven’t yet decided whether to leave the panel flat or slump it. I’m going to live with it for a while before I risk sending it back into the fire. Unlike the great Nampeyo, I’m not sure I could pull this one off again.

Editor’s note: Guest blogger Lois Manno is a New Mexico-based writer, artist, and illustrator. She’s also a newcomer to kiln-glass who’s agreed share some of her adventures in her new medium here. She blogs about her art and other adventures – including cave exploration – at

One Response to Weird, Wonderful Steel Blue Opal

  1. Sheila says:

    Could this piece be fired again with a layer of thin clear and maintain the blue and silver?

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