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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:
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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.
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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.

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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.
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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.
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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.
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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.
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Plain bead overcooked. Made with a HotHead using bulk
propane, cooled in vermiculite and batch annealed at 968º.
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Plain bead slightly overcooked. Made with a Bobcat torch and
annealed at 960º.
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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.
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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.
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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.
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069 Electric Yellow rolled in Ocelot Spots frit blend from Val
Cox.
Made on a HotHead with bulk propane and garage annealed at 960º.
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- Floral Bead: Periwinkle Base with vine stringer. Flower
petals are 204 White topped with
069 Electric Yellow
and , and encased with Vetrofond Crystal Clear.
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- Plain bead rolled in California Poppies Frit from Val
Cox.
Made on a HotHead with bulk propane and garage annealed at 960º.
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Plain bead encased in Effetre Clear. Made on a HotHead with
bulk propane and garage annealed at 960º.
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- Plain 0204 White bead encased in
069 Electric Yellow. Made on a HotHead with bulk propane and
garage annealed at 960º.
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What I now know about this glass
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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. |
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It doesn't seem to matter
what torch is used.
I have fluorescing beads made with a Hothead, Bobcat, Minor, and
Mini-CC. |
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It doesn't seem to matter
what gas is used.
I have fluorescing beads made with Bulk Propane, and Natural Gas. I
have not yet had beads sent in that used MAPP gas or Propylene.
Hint-Hint Hint
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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.
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It's not my "technique" that makes the difference
since others can get the fluorscence as well. |
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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
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From
Wikipedia:
Germanium dioxide is used as a feedstock for
production of some phosphors
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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.
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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.
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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.
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The chemical formula for Germanium Oxide is GeO2 |
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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:
If you want to help figure out when this will or will not
happen, please make a couple of beads using 069 Striking/Electric Yellow, check
them with a UV/Black Light and let us know your results, or you can send them to
me at the address
here.
You can use it as a base color, frit or decoration. It can
be as simple as 1 dot on a white bead or as complicated as you like. It can be
left raised, melted in, overheated, boiled, pushed, pulled, pressed, encased or
not, mixed/blended, twisted, whatever. It can be a wonkie or not - just have fun
with this. I need you to keep detailed notes about what you did, what torch you
used, annealed or not (and at what temp-etc.) and mail them to me so I can test
my findings. Please include the notes about your bead and your business card if
you have one (so I can tie it to the bead to help keep track of who did what).
July 1, 2007
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