The Mysteries of Effetre 069 Electric/Striking Yellow


This page is a work in progress and will change as I get time or find out new information. Last updated Sept. 10, 2007.

I was in my studio one night working on taking pictures of some beads made with Glow-In-The-Dark Powders with a UV/Black light. Not being one to work on just one project at a time, also on the counter was a page from my Frit Reference project. It as open to a page where I had just glued in some beads fro a frit blend I had put together. I had the camera set up, the UV light on, everything laid out and the picture ready to take. I happened to glance over at the beads I had just glued into the reference book and one was fluorescing orange! What the heck? The frits I used were just some Effetre striking colors. Nothing in there should be fluorescing - especially Orange. To make matter even more interesting, not all of the tests for that blend were glowing - only the one that was Overheated. By overheated, I mean held in the flame longer than your normally would, but not necessarily taken to a higher temperature than normally would occur - just longer. The one that fluoresces is on E-204 white, but so are 3 of the others that don't. The colors in this blend are 069 Electric/Striking Yellow, 072 Striking Orange, and 076 Striking Red.

 

I checked the beads and it appeared that it was 069 Electric/Striking Yellow and so I checked the test beads for that color. Sure enough, some were fluorescing orange: Normal, Overcooked, and Reduced.

Here it is in a blend of  069 Electric/Striking Yellow and 456 Rubino. In this one the beads that are fluorescing are Normal, Overcooked, on Ivory, and Reduced.

To help me figure out what's going on here, I put out a call for testers on Lampwork Etc. I asked them to make a bead and to use Effetre/Moretti 069 on it.

Here is what I know about this color:

  • The rods themselves do not fluoresce under a UV light. The Vetrofond version does, but I'm not really interested in them since they fluoresce in the first place. I'm interested in what goes on to change it from non-fluorescing to fluorescing.

  • It's a transparent color and when overheated, this glass becomes translucent. I thought that neither by itself fluoresces, but one bead came in that is a 069 Bead with a simple wrap of a same color stringer - and this one does fluoresce in spots. I later checked an old set of beads I made that included 2 simple spacer beads and one of them fluoresced and one didn't.

              

  • Uranium is not the chemical involved. The chemicals in this case are Silver Nitrate, Silver Carbonate or Silver Oxide to make it yellow and Germanium Dioxide to make it transparent. It works by diffusing micro-crystals of the silver throughout the glass matrix.
                Dunham, Bandhu. Contemporary Lampworking. A Practical Guide to Shaping Glass in the Flame. Vol. 2.  Prescott: Salusa Glassworks, 2003, 474.

  • The effect is not dependent on the batch. I bought my striking yellow when I first started working with glass in June of 2001. Others who have submitted beads for this research bought theirs more recently - of course, I guess it could all be the same factory batch - if it's a slow mover.

  • I checked all the other Effetre colors and the Striking Red and Orange almost-kind-of-sort-of had a hint of a glow around the edges, but it wasn't enough to even tell if the fluorescence was orange or red. None of the other colors fluoresced at all.

The Beads That Fluoresced

Room Light UV Light Details
Hand mixed color - 069 Electric Yellow and 204 White, half and half. It was made on a HotHead using bulk propane, cooled in vermiculite and batch annealed at 968º.
Periwinkle Base. Twist of 069 Electric Yellow and 204 White. Encased with Vetrofond Crystal Clear. Made on a Mini-CC using Natural Gas and an Oxycons. Annealed at at 960º.
Twist of 069 Electric Yellow and 204 White. Made on a Mini-CC using Natural Gas and an Oxycons. Annealed at at 960º.
This one is a Disc built with 069 Electric Yellow, then random stripes of 204 White and 076 Striking Red put on before it was melted down. Made on a HotHead with bulk propane and garage annealed at 960º.
 
069 Electric Yellow base with 420 Coral scrollwork. It's difficult to see in the pictures, but it's not the coral that is fluorescing, but the edges with the yellow and coral touch. Made on a HotHead with bulk propane and garage annealed at 960º.
    069 Electric Yellow base with Vetrofond Pineapple Sparkle swirls. I have since checked and the Vetrofond Pineapple Sparkle fluoresces on the rod so I'm not sure if the 069 is actually contributing anything to the fluorescence. Made on a HotHead with bulk propane and annealed at 968º.
    Plain and simple spacer beads made with 069 Electric Yellow, 4 on a mandrel at a time with a minor burner and tanked oxygen for 4 of them, and a 5lpm oxycon for the other 4. They went straight into the kiln while still glowing a tiny bit, parked  at 960º for up to 4 hours before ramping down.
    420 Coral bead encased in 069 Electric Yellow. Made on a HotHead with bulk propane and batch annealed at 968º.

 

The Beads That Didn't Fluoresce

Details
  • Plain bead melted only till just round. Made with a HotHead using bulk propane, cooled in vermiculite and batch annealed at 968º.
  • Plain bead overcooked. Made with a HotHead using bulk propane, cooled in vermiculite and batch annealed at 968º.
  • Plain bead slightly overcooked. Made with a Bobcat torch and annealed at 960º.
  • Hand mixed color - 2 parts 069 Electric Yellow and 1 part 072 Striking Orange. It was made on a Mini-CC using Natural Gas and an Oxycons. Annealed at at 960º.
  • 069 Electric Yellow rolled in Silver Lake frit blend from Val Cox then encased with Vetrofond Crystal Clear. Made on a Mini-CC using Natural Gas and an Oxycons. Annealed at at 960º.
  • New Violet Base. Twist of 069 Electric Yellow and 204 White. Encased with Vetrofond Crystal Clear. Made on a Mini-CC using Natural Gas and an Oxycons. Annealed at at 960º.
  • 069 Electric Yellow rolled in Ocelot Spots frit blend from Val Cox. Made on a HotHead with bulk propane and garage annealed at 960º.
  • Floral Bead: Periwinkle Base with vine stringer. Flower petals are 204 White topped with 069 Electric Yellow and , and encased with Vetrofond Crystal Clear.
  • Plain bead rolled in California Poppies Frit from Val Cox. Made on a HotHead with bulk propane and garage annealed at 960º.
  • Plain bead encased in Effetre Clear. Made on a HotHead with bulk propane and garage annealed at 960º.
  • Plain 0204 White bead encased in 069 Electric Yellow. Made on a HotHead with bulk propane and garage annealed at 960º.

 


What I now know about this glass

This glass needs to be annealed to fluoresce. All 3 of these beads were made of a half and half mix of 069 Yellow and 420 Coral. I mixed enough to make all three beads from the same pull. The first bead in this pictured is an unannealed bead, the second is batch annealed, and the third one was immediately annealed.

It doesn't seem to matter what torch is used. I have fluorescing beads made with a Hothead, Bobcat, Minor, and Mini-CC.

It doesn't seem to matter what gas is used. I have fluorescing beads made with Bulk Propane, and Natural Gas.

It doesn't seem to matter what oxygen source is used. I have fluorescing beads made with room Oxygen, tanked Oxygen, and with Oxygen from an Oxycons.

It's not my "technique" that makes the difference since others can get the fluorscence as well.

It doesn't NOT like copper. When used or mixed with anything or color containing copper, it turns black.

 


It seemed to me that some colors would encourage the glass to fluoresce, and some wouldn't. In order to find out whether or not a color would, I decided to mix some up to see if the combination did. I made a bead of the resulting mix for each color in the Effetre/Moretti palate. Here are the resulting charts - the ones with the names highlighted in yellow were the mixes that fluoresced. Each mix is half and half. I did end up with enough interesting color mixes to make the charts interesting for the color mix project as well.

   


Some Technical Stuff

From Wikipedia:

Germanium dioxide is used as a feedstock for production of some phosphors

From Encyclopædia Britannica:

In addition to its applications in electronic devices, germanium is used as a component of alloys and in phosphors for fluorescent lamps.

From Yohkoh Analysis Guide:

1.4.3 Germanium Fluorescence
When germanium is illuminated by photons whose energy exceeds 11.2 keV, the crystal fluoresces, emitting a photon whose energy is 9.9 keV. Since the energy resolution of the BCS detectors is around 20%, the tail of the distribution of these fluorescent photons falls within the energy range that the BCS is sensitive to and indeed part of the tail lies under the distribution of the photons detected by channels 1 and 2. In order to try to reject the fluorescence, the upper level discriminator is set midway between the two energy distributions. germanium fluorescence is less of a problem in channels 3 and 4 since there is a greater difference in the energy between the channel photons and the fluorescent photons.
 

From Electrical Engineering Training Series:

This principle is used in the fluorescent light where ultraviolet light photons, which are not visible to the human eye, bombard a phosphor coating on the inside of a glass tube. The phosphor electrons, in returning to their normal orbits, emit photons of light that are visible. By using the proper chemicals for the phosphor coating, any color of light may be obtained, including white. This same principle is also used in lighting up the screen of a television picture tube.

The chemical formula for Germanium Oxide is GeO2
According to Sylvania, the chemical formula they use in in lamps to fluoresce red is Mg4(F)GeO6:Mn

 


I would like to thank the following people for submitting beads or contributing ideas:

Nikki NLC Beads
Jayne Jayne-0-

July 1, 2007

 


You can contact Kitty by emailing her at kay@listen-up.org.

 

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