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Paul Stout 08-10-2019 09:22 PM

Blue Sulphur
Weyl, in Coloured Glasses (pg. 257-258), and Volf, in A Chemical Approach to Glass (pg. 538), describe making a pure "ultramarine sulfur blue". They both point out that this is done in "borate melts". So my questions are a)has anyone here ever tried this? And b) Is a "borate melt" a batch that contains borax/boric acid or is this implying that it's only attainable in borosilicates? Im going to be doing some sulphur melts/experiments in the next month and thought I'd give the sulphur blue a try, if anyone has any experience to share, I'm all ears. Thanks!

Pete VanderLaan 08-11-2019 07:18 AM

I have never done a melt in sulfur that did not do one of two things.
A: make an Amber
B: Really stink up the joint.

I'll read about it. If it does do what you suggest, it would likely be in a boron based glass but I have never heard of it.

Paul Stout 08-11-2019 10:58 AM

ďThe process for making these glasses is quite simple. Sulphur, or an alkali sulphide, is dissolved in molten borax, and into the brown melt excessive boric oxide or phosphoric oxide is stirred. The color changes at first to dirty yellow, then to Grey and finally into a pure blue. This blue color being due to elementary sulphur cannot be obtained in glasses which contain major amounts of zinc, cadmium, or other ions of heavy metals with a pronounced affinity for sulphur.Ē
-Coloured Glasses, Weyl, pg. 258
Sounds like a fun, if stinky, experiment if nothing else!

Bradley Howes 08-11-2019 02:37 PM

A borate glass, as I understand it, is a single component glass that is made up of B2O3. It melts into a vitreous soup at 450ļC (842ļF). Strangely, it has a coordination of 3, that means for every boron atom, it is bonded to 3 oxygens.
I've used boric acid as a flux to purify some gold. The gold formed a bead at the bottom of the crucible and the glass above it dissolved most everything that wasn't gold. When this glass is poured out of the crucible, it starts off perfectly clear and transparent but within an hour, the surface becomes cloudy because it absorbed water from the air. For any glassblower that primarily uses silica as their glass former, borate glasses aren't compatible in any way.

Josh Bernbaum 08-12-2019 12:54 PM

Copper and cobalt donít smell.

Paul Stout 08-13-2019 10:10 AM

Thatís true, and I do love copper blues, but Iím going to be using sulfur in the traditional way anyhow, so why not try (in the quest for knowledge and understanding and such). Also supposedly the blue comes from elemental sulfur which doesnít stink, only itís compounds do, so theoretically this sulfur blue wouldnít smell either. But not having done it yet, I donít know. Iíll post results, good, bad or indifferent just in case anyone else is interested.

Eric Trulson 08-13-2019 05:16 PM

I applaud your curiosity Paul. Please do post your results.

Personally, I'd be really curious to hear about how the borate glass handles compared to a silicate glass, in terms in terms of its viscosity and stiffness and how it blows out.

Pete VanderLaan 08-13-2019 07:34 PM

Here's what I think really needs looking at:

Both Mark and I have been really interested in the effects tha changing out the conventional fluxes and stabilizers do to color.

Fluxes- get rid of sodium- it's just a junk material. replace it with other light metal from the first column- potassium ,lithium.
Then look long and hard at the stabilizers. Look away from calcium. Look to Strontium, zinc, any thing in the range that can stabilize glass using differing metallic materials. Look to barium. The color work lies in there for incredible variations. use them.

Blue Sulfur is a sex toy. It won't change American art work. If you wind up casting, these differing pursuits will change the world. No one has done it because it costs money.

You just can't do this stuff with cullet, or commercial batches like SP. It boxes you in before you start. Get a simple mixer. Think outside of the place you started but a few of us have suggested you pursue. You are the future.

Paul Stout 08-14-2019 12:53 AM

Today the Mobile Mini arrived and we began retrofitting it with ventilation, door, lights, shelves and. . . A mixer! Along with scales etc. So needless to say Iím very excited. Ive been mixing colorants with batch outside in buckets, with decent results but this is going to let me get scientific in my approach. Thanks for the words of encouragement Pete and Eric, Ive been blowing glass for 20 years and have been a bit stagnant the last few years, but this new world of making my own colors has been nothing short of thrilling. And now Ill have the facilities and a bit of financial backing to try some of the things Pete is suggesting.

Iím looking forward to making glass from scratch and can do small test melts with some different fluxes and formers. Thatís probably enough to keep me busy for the next couple decades. One of the things mentioned is that this sulfur boric acid acts as a flux and so I thought with some tweaking I might get it into a simple recipe.

Since Ive been making color Iím thinking and sketching more and more in terms of casting, so funny you should mention it. I love the idea of smooth gradual color shifts from ultra light to ultra dark or from one color to the next, simple but profound. Iím certainly not out to change the world, I just want to get closer to the magic, and the magic starts in the mixture.
But if I manage to pull a blue out of Sulfur Iím definitely naming it ďSex Toy BlueĒ

Pete VanderLaan 08-14-2019 09:20 AM


Originally Posted by Paul Stout (Post 144967)

But if I manage to pull a blue out of Sulfur Iím definitely naming it ďSex Toy BlueĒ

It will sell well. Make sure you send the royalty check to the right place.

Eben Horton 08-14-2019 10:02 AM

Sex toy blue would sell, but perhaps you have to make the name more artsy... for example dale chihuly renamed cooper ruby to oxblood.

Just thinking out loud.

Pete VanderLaan 08-14-2019 10:30 AM

Oxblood is actually a very old name for a copper glass that hematonized and went to a livery opaque. The molecules just get too big and they reflect light instead of allowing transmission. The term is used in ceramics as well.

Shawn Everette 08-14-2019 12:05 PM

I had an ancient Kugler bar that was an opal oxblood. Never found a glass it was compatible with, craze if cased, jump ship if it was a lip wrap. Was having problems with a color thief, made sure it made it to their collection.

Pete VanderLaan 08-14-2019 12:26 PM

Color thieves seem to be an institutional problem I've heard of frequently. I'd like to hear more horror stories.

Greg Vriethoff 08-14-2019 02:28 PM

I've never had anyone steal any materials I've left laying around. I have had finished pieces stolen from ware racks in public access settings.

When I did a workshop at Fresno State back in 2005 we were doing some sessions of figure drawing from live models in one of the studios (the theme of the workshop was The Human Figure in Glass). I left one of my finished drawings on the easel I was using and went to lunch or something. It was gone when I came back later. I mean, I'm flattered someone liked it so much, but I would have just given it to them if they asked.

Shawn Everette 08-14-2019 02:49 PM

That place was particularly problematic. We had to file two restraining orders during my tenure. It was really more of a generational thing, most of the new people we had around were fine. Definitely a case of way too many drug fried brains, and not taking the drugs you're actually prescribed. It ended up cleaning up nicely, but there were several tumultuous years.

There was a guy that used to try and live in his studio. You'd come in and there'd be a clothes line strung in front of the furnace. He would openly show people spaces you could freely move through the studio or how slow you had to move to not trigger the motion sensors.

Pete VanderLaan 08-14-2019 03:42 PM

I recall Josh Simpson doing a workshop at one of the schools and someone lifted his Dino jacks from the bench during a break.

I've heard stories at R.I.T. We never had any problems at Pilchuck except stealing ideas. I used to have issues with people looking in our supplies and writing down the material sources we used without asking. Given that, I would leave out stuff that didn't work and put the good stuff away.

Shawn Everette 08-14-2019 04:32 PM

There was the day that I came in to see that someone had shot our vending machine. Though it Looked like it came from about a mile away judging by the trajectory.

Had a guy get a fan yanked out of the ceiling because he got a retractable cord caught in it, tried to blame me.

A relatively well known blower stiffing their bill because they said glass was cracking, I told them before they started their color of questionable compatibility, used it anyway. His assistant would use the block water to bathe himself.

Had a few just regular retail thefts. There was a hilarious one where this group of kids stole a ring, then came back to get the matching one after they thought they got away with it. They were actually interested in glass, so my boss conned one of them to sign up for the mailing list. The cops couldn't stop laughing when they were describing their interaction with the mother. Kid's ass was red that night.

Pete VanderLaan 08-14-2019 05:37 PM

I think, in retrospect that the shows were really the worst contributor to intellectual theft. Chuck color aside. It was rearkable in the mid '80's to mid '90's to see work lifted wholesale from one booth to another.

The stores were happy participants. If they could get a badly made fraud, they took and promoted it. I think GAS was among the worst offenders in their annual auctions. They didn't have the pull that the Pilchuck auction did so they were major whores for wannabes.

That stuff was everywhere. I had my sharp beveled edge work lifted at one of the shows by a shop getting a piece in of mine for repair. It did not take long for stores to remark on how I had stolen the style.

Anyone remember the actual facts about OCR beginning to sell Kugler? Yesterday I heard from someone claiming they were an early distributor for Spruce Pine. That's pretty funny.

Now that Bomma is available , look at who's getting shut out.

Greg Vriethoff 08-14-2019 11:48 PM


Originally Posted by Pete VanderLaan (Post 144980)
Anyone remember the actual facts about OCR beginning to sell Kugler?

No. But I know why they don't sell it anymore.

Rich Samuel 08-15-2019 11:01 AM

In the late '80s, Pratt was heaven for thieves. I had a virgin punty stolen before Steinert had time to cash my check, and if you wanted to keep your unused color, you kept a frax-lined coffee can in your gear so you could take your color with you when your slot ended. I arrived for a slot once and the earlier group was laughing about a kid who was found in the parking lot "sharpening" a pair of jacks on the concrete. Fortunately, the pair he swiped was Pratt's, so he may have actually improved them. :D

Bradley Howes 08-17-2019 12:03 PM

Im going to take a stab at this sulphur blue either tonight or tomorrow, depends on what time I finish my drive back to Alfred. My big question is how much sulphur should I use? Iím thinking between 1-5% which is probably over kill but I have no idea. Iím planning on mortaring the sulphur with some boric acid. The sulphur we have is as chips but clumps together unbelievably in the mortar. From there, Iíll mix it into the rest of the boric acid and charge it. Any thoughts?

Paul Stout 08-18-2019 02:44 PM

Bradley: awesome, you're ahead of me. It'll probably be a three weeks before I get to trying it. The notes I have so far in no particular order
1. the blue is due to elemental sulfur.
2. the blue appears in borates when Na2O is less than 26 mole-% (volf pg. 538) (I don't know if this is fundamentally different than 26% by weight maybe someone can help here and if so might be a sticking point).
3. There can be no zinc, cadmium, or other heavy metals with an affinity for sulfur because they will form compounds and eliminate the elemental sulfur
4. If B2O3 (boric oxide) is introduced to into a silica-containing glass it acts as a flux (Weyl pg. 33).
In terms of amount I have no idea, I was going to start with using the dissolved sulfur/borax mixture described in Weyls book (and quoted a few posts above) and use it for the borax in Vanderlann's clear recipe which I got from craftWEB:
63.25 silica
20.25 soda ash
9.06 Hydrated lime type N
2.18 Borax 5 mole
5.25 Potassium carb
100 grams antimony oxide
130 grams potassium nitrate.
I have no idea if this will work, but its where I was going to start.

Paul Stout 08-18-2019 02:53 PM

One more note, acidity is sulfurs friend. Polysulfides form in alkaline melts (yielding other colors like amber, brown etc.), so getting the alkalis low and acids up is going to be key if this is going to work.

Pete VanderLaan 08-18-2019 03:38 PM

well, that batch of mine, which I haven't really used since around 2004 is chock full of bases, not acids. I can see sulfates and sulfides forming in lots of spots.

I'm still not really clear on what you call elemental sulfur. Exposed to atmosphere most elements combine with the atmospheric moisture, or combine with other elements. I don't know how to do that without issues. The only sulfur I've ever seen is yellow up around the helper point on the DRG &W in western Colorado. Lots of it there.
I will be fascinated if it works and does something useful.
I'm fuzzy on it but it seems to me that the 9.06 on the lime referred to actually calcium carbonate. It would be less if it was the hydrate since it gets more calcium per weighed lb than the carb does. It matters. 6.78 lb rings a bell. It's been a long time since I've considered that stuff but I think you should examine the percentages in the formula. I'm a bit spent from an afternoon making sconces for a wedding.
Mole chemistry has you add up all of the atoms in the proposed mix and then calculate the weights of them. It's quite different than doing percentages by deadweight. It does make one appreciate how much oxygen is in the glass. If you go that route, best to use Appen for your expansion factors.

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