Schmaltz!...from cullet?

[Dave Bross]

Probably mainly a Pete question but who ever knows what other elders lurk...

If you were going to try for a schmaltz or a veiled silver transparent from cullet...what would you suggest. I'm determined to do something with all that drop bucket waste.

A trip through the archives suggests the difference between veiled translucents and schmaltz-like opals is the black tin. I haven't tried it but I'm thinking the black tin is probably like it's more oxidised white cousin in that it's not going to melt into cullet? Does that take us back to dumping anything we can find that has much carbon in there for reduction? Any thoughts on the veiled transparents would always be welcome too.

We know we need iron and , of course, silver nitrate (duh!)...I remember reading that sulphur will help opalise if you get the strike temps and sequence just right (like spectrum red/yellow/orange color cullet...sometimes I can strike it opal w/swirls...sometimes not...always not when someone wants something like that quickly) and don't put in so much sulphur that it becomes a pain to keep from reboiling. What about tin in its metallic form?

Here's an old Fritz recipe, I'm assuming from batch:

1/8 % silver (.125%)
3/4 - 1/2 % copper (.75 to .5 %)
1/10 % sugar (.1%)
1/4 % cobalt when it works (.25%)
Decrease calcium and magnesium
Increase zinc and Barium

So we have some copper in this one, no iron and no tin.

More different oxides = more different colors? specific oxides = specific colors?

[Eben Horton]

you will get Iron from your moil crack offs. Especially if your pipes are steel and not stainless.

[Dave Bross]

Yeah, I was thinking that the random odds and ends in the drops might be an enhancement too.

[Pete VanderLaan]

add the iron. The earliest schmaltz glasses I got were from plate glass which had the iron. Black tin will go into a cullet easily. White tin will not. If you want to add it in the easiest fashion, Stannous chloride will give you an easy intro of stannous oxide once the Clorine gasses off. The chloride form is far easier to obtain for most people. Nasty crap though.

[Dave Bross]

Thanks Pete!

I've got black tin so that'll to be the easiest way.

Forgot all about stannous chloride but I think my poor old wire melter (and its owner) would be far better off without having a good gassing with chlorine.

[Barb Sanderson]

Forgot all about stannous chloride but I think my poor old wire melter (and its owner) would be far better off without having a good gassing with chlorine.

Whew! I thought you were going to show up at my studio tomorrow to make this stuff! You really need to see the color that came out of the annealer sometime before you head back tho!

Barb

[Dave Bross]

Barb,

I'll be here until August 4th, temporarily gone for the weekend of 25/26/27 maybe 28 for the Ellensburg jazz festival. I do want to get a look at those colors.

[Garner Britt]

I've long known chicken fat as Schmaltz but did a wiki search to find this

http://en.wikipedia.org/wiki/Schmaltz

some reference at the bottom about those old school sequin signs.

what is "Schmaltz glass"

any examples?


garner

[Dave Bross]

It supposedly got its name from the rainbow effect of grease floating on water.

It's a swirly multicolor opal if done with tin or a veiled transparent/translucent without tin. Sort of like a lot of what you see in a lot of Raku pottery

It changes with different reduction/thermal history (strike) and is quite sensitive to this.

There is/was a good pic of it on here somewhere of some work that someone who used to work for Pete made with Pete's recipe but I can't find it now.

Reichenbach makes a glass that is likely a schmaltz, or at least it gets much the same result. it's R 108 Iris Orange. If you look at the example of R 108 on Phil's website ( http://www.glasscolor.com/products/default.aspx?cID=22&pID=370) don't go by that...it's overstruck. If you go too far on the strike you get tan or brown.

[Jon Myers]

Hey Dave, try some TiO instead of iron (say .7g per 50lb) It will take longer to strike opal and you will get a wider, more controllable (with heating and cooling) range of color. The Ti is a much smaller seed than the iron. It also stays less brown when it goes opal. If you nail the black tin/sugar% you can have a glass that plates silver (a trait of a oxidising body) or opalizes (a reducing body) (I guess it would make it a N to slightly O- body) depending how you treat it. A small window that would probably be hard to deal with with knockoff as you have no way to keep things consistant. (But doable with a known feedstock like 101SFS)

[Pete VanderLaan]

I am assuming you mean titanium. what do you mean exactly when you use the term "N" and "O" body? Neutral and Oxidizing?

[Dave Bross]

Thanks Jon!

I've been searching for something to slow down striking in general and I REALLY appreciate that particular tip and the explanation of why.

I know some of the old glass factories had/have some silver glasses that were very reliable and very slow striking. Fenton Fabrene is a classic example.

What little experimentation I've done is pointing to what you said about how exact the oxygen (or lack of oxygen on into reduction) has to be. Pete has made that point in the discussions on selenium rubies a while back too.

I had no idea more precision in the oxidising/reducing situation could take you from plating out to opal, I thought you had to load up the glass with silver and tin to get plating.

I've seen old corresdondence between factory glass chemists and some of the old small shops (Thanks Rollin!) on situations where the chemists were solving problems for the shops. The chemists always made it a point to figure and list the oxygen content of whatever batch they were all working on. I'm guessing it was done from mol %. Looks like it's probably time to build that capability into my spreadsheet.

I'm figuring O = oxidising N = neutral (no oxidisers no reducers) R = reducing

You lost me on "(But doable with a known feedstock like 101SFS)"

One other thing I forgot to mention in the prior post. If you want someplace to start (and some pics of the results) on striking the R - 108 Iris Orange, Google or look on the beadmaking boards under "raku bead" . That will give you a place to start technique-wise, with the caveat that on this particular glass it's a lot easier in the high heat and greater oxidising/reducing adjustment available with an oxy/propane lampworking torch.

[Jon Myers]

yes R is reducing O is oxidising and I'm indeed refering to Titanium. I find doing most of the reduction with black tin and doing the last little bit with sugar helps make finding the "sweet spot" a little easier (OOOOH Bad Pun) as a gram of suger hs less effect on the glass than a gram of black tin. I also find a bigger batch easier to do than a small one (likely from ingredient distrubution issues with silly small amounts of the Titianium)
the 101 sfs is Spectrum fuseable clear cullet
a little water makes it melt smoooth

[Dave Bross]

Jon,

Thanks, got it!

If you don't mind, what percentages of silver and tin are you using to get that shift from opal to plate?


I've been using phosphorous as a seed starter for copper ruby. I'll try the titanium next time around. Slower striking there would be a big plus.