Hello! Yes, that’s right, this is actually a glass related posting. Funny world, eh?
So let’s get into it. There’s a company importing Indian glass now, called Devardi Glass. They started with soft glass in the 104 range, and I haven’t tried it. There’s mixed reviews, folks who love it, folks who hate it. Frankly if you work soft glass you probably know someone on both sides, so find a hater and buy their stash if you’re interested. There’s precious little middle ground.
More important to me, they’re importing borosilicate, COE 33 glass too. The price is certainly right, but I’m also mindful of the “you get what you pay for” adage. Still, I got a good deal on some Colormax color a while back, and while there was a fair amount of junk, the Colormax white is my absolute all time favorite white glass. Work boro for a while, and you’ll find that’s one thing everyone has a personal favorite on.
I’d like to point out at this point, I don’t know the owners of the company, so far as I know they aren’t on my Facebook list, I didn’t receive anything for free, this is simply me reviewing glass I paid money for.
The glass is inexpensive, I had the extra money on hand for a change, and I like to experiment. I’ve worked a variety of stuff including bottle and window glass, so I like new things. Here’s what I ordered:
Quarter pound
- Transparent cobalt
- Lily pad
- opaque turquoise
- opaque medium brown
- opaque orange
- opaque black
Rod
- opaque red
- opaque lemon yellow
- opaque light pink
- opaque mango
Full pound
Quite the mix, I know, you’re jealous. Mostly it was a mix of what I thought was interesting. In the case of the orange, lily pad, and turquoise, I’m curious how it works. Cobalt and black can be tricky in their own right, and the white…well I was hopeful it was my new stash. We’ll get back to that.
Quarantined to the cookie sheet for now so it doesn't get mixed in with my other glass
I wound up getting my glass a day ahead of when I was expecting, which is always nice, and it arrived intact. Zero breakage is tough to do, so I was happy.
The first thing I noticed about the glass was the striations in the rods. Lines aren’t that odd, but striations? That’s different. If you look down the center of a rod of this glass, you can see veins of clear. Normally from a pot of glass you should see some fairly homogeneous appearance. Occasionally you get a line of clear through a rod, but this isn’t the norm. It’s almost as if rods of clear and color were bundled together, heated and pulled down instead of being drawn from a molten pot of glass. This cropped up later, most notably in the white glass where it cleaved along some of the clear lines while applying in the flame. This is a less than desirable feature.
These are some drops pulled off the rods once I had cleaned up the ends.
It's not supposed to look like a colorful sperm parade, honest!
This is a side view:
Left to right: Lily pad, white, turquoise, orange, black, brown, cobalt
Here’s the breakdown of what I’ve found so far. There’s another batch of tests in the kiln via spacer beads so I’ll report more tomorrow or so.
Overall: The rods were a bit grimy and I cleaned what I tested with some glass cleaner and a paper towel. Given the rods are hand pulled, they are of varying thickness. While I was careful introducing the thicker rods into the flame, the turquoise fairly consistently had some popping and cracking as it was heated. Extra caution helped with this, but it wasn’t a total solution. For this test I kept it either to a single color, or mixed with another Devardi color.
Opaque white: Yellows easily, and even with mixing, the clear doesn’t mix in well leaving lines in the finished product. Drill mixing might help this, but that seems excessive. Truth be told, the jury’s still out on this one. Have a look at the following picture. You’ll notice the white’s pretty white in the blue/white marble. In the green one it stayed yellowish. I noticed this yellowing on samples I pulled off the rod too, so it wasn’t a spillover effect from the green.
If you look at the green/white marble, you'll see the clear lines I mentioned
Cobalt: This was another odd color. It’s a transparent, but usually cobalts are fairly simple to work. Sometimes you get some reduction, but turn up the oxygen and it’s usually dealt with. With this, it devitrified as it was being applied. The small samples I pulled showed discoloration, and at first I thought it was reduction, but as I later applied more, I saw the tell tail appearance of the desaturated, washed out, matte finish. Here’s where it gets weird. I pulled a stringer of white and applied the cobalt over that. I saw plenty of messy, devitrification. I attached a small bit of white to the end of that, melted it into a marble and it smoothed out. On the other side of the kiln cycle, you see the marble above. Clear, vibrant color. Very odd.
Black: Overall this worked very nicely. When thin you can tell it’s a heavily saturated blue base. When thicker it’s pretty well opaque. I didn’t notice any reduction problems, but the first set of tests were pretty limited.
Turquoise: Of the handful of colors I tested up front, this was the only one that I had a popping/shattering problem with. I have worked with some turquoises before, so I wasn’t too surprised, nor was I surprised when I saw a little bubbling/boiling. I was happy to see that it held it’s color pretty well, very WYSIWYG overall and working cooler helped with the bubbling. Careful entry into the flame helped with the popping issue to some extent, though later on I did have some problems with the rod “chunking” while I was messing about; that is the rod would sometimes break half an inch or so up the rod while working. One problem I’ve had problems with turquoise is reduction; the glass loses some of it’s color and goes to a rust/red color. I’m happy to report this held its color very well.
Orange: This color was a nice surprise. I’m horrible with cadmium colors, it’s a lack of experience, so I tend to avoid them. Oranges tend to boil easily too, so this was going to be a challenge color. However, a cooler flame and gentle introduction helped keep the color from boiling other the occasional bubble coming to the surface. The color holds very well, it was not bad to work with.
Lilly pad green: This was a fun color to work with. Again, it had to be worked cooler to avoid boiling, but once that was sorted, it was pretty usable. I was concerned about the green reducing down to a red color, particularly because when it’s hot it goes brown. But once cooled it stayed a vibrant green.
Third from the right shows the bubbling
Opaque light brown: I only played with this color long enough to pull a sample off, but it was heat tolerant, and stayed a lovely dark coffee/caramel color.
So what was my overall opinion? So far, not bad. That cobalt’s a bit of an enigma, so I’ll need more testing, and the white’s not making any friends around here. But the other colors were surprisingly good. I was particularly impressed by how well the brighter rods held their color.
In the second round of testing I made more spacer beads, but I tried mixing a couple of the colors as well as introducing some Simax clear. Tune in next time for those results.
Have fun, and keep your fingers out of the flame.
