Playing with glass blocks
September 6, 2009 by cynthia

Fresh-from-the-kiln color samples (well, I coldworked them a bit) These are mostly earthtone pate de verre shades I'm testing for a client.
The reward for patiently, carefully weighing and mixing and packing frit into little plaster cells, then documenting the result? You get to play with blocks (right).
Those of you who’ve been to the studio know my obsession with color tests and frit mixtures. I have LOTS of these little things.
The cool thing about frit is that it can hide or show the true nature of the glass. In sheet or rod or cast form, black glass looks, well, black. Stretch it thiiiiiiiiin, though, or cut it with enough clear…and you get dark violet.
Baby-poop brown (NOT my term, a friend calls it that) makes one of the most beautiful clear saffrons, dark blues dilute to periwinkle, etc. And the only way you’re gonna know this stuff is to test it.
34 of the samples in the above picture were made with about eight colors of frit. (The 35th, the little blue tile at bottom left, is a Gaffer lead crystal sample I needed to test for another project.)
I once tried to build a full catalog of readily available tints but it seemed to be a never-ending battle; every time I’d think I’d nailed one color of glass another permutation would pop into my brain. At 7K plus samples, I hadn’t even started the blues yet.
So I sat down and figured out how many combinations I should test:
- Total number of Bullseye glass frit colors: 109
- Total number of Bullseye frit sizes available: 109 x 4 + 1 (Extra coarse clear) = 437
- Standard frit tint test panel: 10 tints (0%, 1%, 5%, 10%, 15%, 20%, 25%, 50%, 75%, 100%)
- Total number of standard BE single color frit tints possible: (437 X 10) ^ 108 = 1.5e+285
Uhm, that’s a really big number. Bigger even than the US deficit. Add in all the possibilities from an additional 241 Uroboros 90 frits, and the calculators stop giving me numbers and just say “infinity.”
Or in other words…a WHOLE lot of possibilities.
Now, realistically, not all these combinations will produce tints that can be distinguished by the human eye. Some of them will be splotch-on-splotch instead of true frit tints. Many will react with each other to produce the same sludgy brown, grey or black. Too many involve opal on opal, which cuts translucency to zero in pate de verre and makes the piece look painted. And some are, frankly, just ugly or really, really blah.*
In fact, far less than a tenth of those possibilities are what I’d call “practical tints,” i.e., stuff that I might want to put into my pate de verre.
That’s still a lot. And that’s only for single-color tints.
Now add in multi-color tints, which is mostly what I use, and you head right back to infinity. Plus, whenever I have a solid color field I tend to “drift” the color, i.e., combine lashings of pure color with frit tints in layers, to add depth and interest.
So if I do nothing but make color tests constantly, keep four kilns going without stopping, until I’m 98…I probably STILL won’t get to the blues. Sigh–now I don’t feel like such a slacker.
A year or so ago I abandoned the classic wedges and ice cube, for flat tiles with texture. They’re better for visualizing how the color will look in a real piece, and the changes in thickness give you an idea of what some depth will do to the shading. They let you play with surface finishes–firepolish gloss on the smooth back, coldworked, velvety smooth fronts.
The results are infinitely more satisfying on many, many levels. I like looking at them, handling them, arranging and rearranging them, checking the way the light passes (or doesn’t pass) through them. And I’ve noticed other people like playing with them, too–one neighbor plunged up to her elbows in color samples last week, saying “They just feel so good.” (One buddy asked if she could string one as a pendant and wear it–’way too heavy, but hey)
So…I’m working on ways to exploit that. In the meantime, I need to get these things up on the wall because honestly, I think they look good just massed like that. I’m gonna get them mounted, maybe even make up sets for sale. We’ll see.
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*I was politely chastised for accusing Dense White of producing tints that were “nasty” and “dead-looking.” It does that for me, despite the rest of the world’s ability to use it to make ethereally dreamy pieces I love. Of course, in my youth I was also clobbered for telling a doting mother that I wanted to photograph her toddler because he was so ugly he was adorable. I have since developed more tact but apparently only for people’s children, homes and small animals. When it comes to peoples’ glass, I seem to be just as brutally honest as ever.
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Wow! Even if you could get to all of the samples, where would you put them?
I do love this and how you keep track of it all. Invaluable.
Looks like a beautiful box of candy, Cynthia!
Cynthia, I love your work and I admire tremendously your ability to research and develop materials and product, for your work. I don’t personally know many successful glass artist but I do think the key element in being successful in terms of controlling and creating the results you expect, is the willingness to spend vast amounts of time experimenting. I have seen the results of this at Bob Leatherbarrow’s studio. He has numerous test tiles that he has made over the years, identified and mounted and when I took a course there they were a great help in selecting colours. I have started to develop my own tiles but I do get sidetracked when the desire to produce something overcomes me and I just charge ahead to create something for instant gratification. Patience is indeed a virtue. Sorry for the rambling and I do know there are other artist out there with similar work ethics like yours and it’s probably their work I admire the most. Mary Lou
Thanks, Mary Lou…it’s a little easier to do it as a caster, I think. I have ready-made forms for test tile molds, and they stay set up in my mold-making area. Any leftover investment immediately gets slopped into the tile mold, so that after three or four molds I’ve got another blank for tests. I pretty much turn one out every week or so, possibly more often.
There are times, though, when I think I’m doing more testing than actual making, and that gets frustrating.It’s only been in the last six months or so that I’ve started to be able to predict what the glass will do without making a bunch of tests (and be reasonably accurate) in the warm ranges. I’m still working on the cool blues.