Is shine from reduced glass permanent?

glassbead · #1 2009-09-06, 1:33pm

I just read this the other day on the BOC site- is this correct?

"Please avoid using reduction glass, frits, powders or enamels that will leave a metallic surface on the beads. These metallic surfaces tend to wear over time and we want your beads to remain as beautiful as the day that they were made."

I've never heard anything about it. If so, I don't see how we can sell beads made with reduction glass that has been reduced. Folks would not be happy to see their beads slowly but surely losing the shine they loved.

*Naos* · #2 2009-09-06, 3:07pm

Yes, the shine can be lost over time, especially if worn against the skin or exposed to water for long periods of time.

RSimmons · #3 2009-09-06, 3:39pm

Yes, the surface does wear. As a rule it is no more than a few micrometers thick. It's also not all that uncommon to find that the shiny metal surface is elemental lead.

Robert

Elizabeth Beads · #4 2009-09-06, 4:21pm

A silver cloth will restore the shine on reduction glass. To avoid losing the shine, wash off any oils from wearing the bead against your skin, dry thoroughly (a hair dryer works well) and store in one of those little ziploc bags.

But for BOC it would be best to avoid using it.

glassbead · #5 2009-09-07, 12:19pm

Hmmm... Sounds like it would be best to avoid it, period. Especially if wearing it against the skin will cause it to wear off. Where else is a bead going to be worn?
I had never heard anything about this. It is good to know you can bring the shine back up. But lead? Really? I thought what caused the shine was silver content in the glass. Maybe not so much?

squid · #6 2009-09-07, 1:56pm

The shine is caused by metals in general, not just silver. Not sure how much lead is involved, but I don't think most of the shiny glasses are leaded.

RSimmons · #7 2009-09-08, 5:56am

You might be surprised. Lead and zinc are both pretty common in soft glass. Some 'silver' glasses contain silver and right carry that name, other 'silver' glasses are called that because they look silver. The metal may well be lead, zinc or manganese, to name the most common ones.

Robert

truegem · #8 2009-09-08, 7:07am

One advantage to silver glass, though, is you can always encase it.
I hardly ever leave them exposed anymore, I usually like the encased look better.
Except for Triton......::sigh::

NMLinda · #9 2009-09-08, 8:06am

If you don't want to encase, is there another way to protect the surface, say, with a hard wax?

Linda

SilverReflections · #10 2009-09-08, 8:30am

Well I never thought about using it for the metallic finishes but I use Renaissance wax on the copper from my electroformed pieces to maintain the patina. Now, I'm curious I'll have to try it on a triton bead and see if it does anything to the metallic effects when put on which is what I think may happen...

Tina

playswithfire104 · #11 2009-09-08, 9:07am

How long does it take to wear off? I have a bead I made in the Spring and have worn it almost everyday. I sleep with it on and swin and get in the hot tub with it on and it still looks as good as it did when I took it out of the kiln. Is this something that happens over years?

ptrautman · #12 2009-09-08, 9:26am

I can tell you that TAG has no lead added to it. I have seen what appears to be lead bloom in a color or two from another manufacturer but you have to ask them. However, it is getting rare due to the toxicity of and regulations on lead. It can do nice things in glass however.

In my experience lead "bloom" usually has a grey color to it. Silver tends to be like a shiny mirror, yellowy or white on the surface if heavily reduced. With experience it is fairly easy to tell.

As far as the wearing off of the shiny layer... interesting topic. I really don't know how fast that would happen. This would also depend on the thickness of the layer and the type of chemicals rubbed on it as well as time. It also depends on the other chemicals in the glass formula as well. I add several substances that increase adhesion of the silver layer to the substrate. Maybe I should add more? How big a problem is this?

Someone should devise a standard testing procedure.

RSimmons · #13 2009-09-08, 9:43am

The testing that I have done personally has been using Energy Dispersive X-ray Analysis (AKA EDS/EDX). X-Ray Fluorescence is the technique used by CPSC testing labs and is very similar.
Lead may present a very shiny surface and may appear to be either silver or gold, depending upon the distribution of the metal on the surface and, to some extent, the thickness of the layer.
Wear-off will depend on the type of metal, thickness of the layer, amount and type of wear, exposure to skin or rough fabrics, etc. In light of the CPSIA rulings in the last few months, wear-off time is of less importance than the fact that the metal is present at all. According to the CPSIA the very presence of lead on the surface is a HUGE problem.
I've been talking with several microanalysts about this issue, including some at NIST, but I don't think that there will be a major testing effort without some sort of funding to support it.
The bottom line is that glass workers need to learn more about the materials that they work with. Many of the manufacturers need to be more forthcoming about the metal content in their glass (some already are). Don't assume that gold color is real gold, silver color is real silver, etc. Ask questions and demand straight answers.

Robert

NMLinda · #14 2009-09-08, 11:38am

In case some of you missed his posts on this, Robert has tested several colors of glass and graciously posted his measurements here on LE. You might find his results quite interesting - worth doing a search to pull them up

Linda

RSimmons · #15 2009-09-08, 12:24pm

I'm working on a technical article that addresses metallic surfaces on art glass but it'll be a while before it gets published. We've still got data to collect from a couple of new technologies that complete the picture.

Robert

Firebrand Beads · #16 2009-09-08, 1:17pm

THANK YOU, Robert!!! I can't wait to read it!

RSimmons · #17 2009-09-08, 5:17pm

It'll be a while - after it's written we have to submit and go through the peer review process, then wait for publication.

Robert

Firebrand Beads · #18 2009-09-09, 12:54pm

GADS I love hearing "peer review" instead of "rushing it out" LOL!!!
I will be patient. ;-D

ewdb · #19 2009-09-09, 1:38pm

i've only had an issue (to date) with Effetre dark silver plum (DSP) - that lovely irridescent finish came off almost immediately just from cleaning the bead holes. I did one (highly unscientific) test where i soaked a bead made with DSP & DH Triton in tap water for a few weeks. the Triton was fine (although some of the dots did begin to react a bit with the minerals in the water near the end) but the DSP metallic finish was gone within a couple hours and just the purple was left. I've decide to substitute Triton for DSP from now on...

One thing i did note on another bead though was that where the Triton fumed the metallic DSP the colour remained longer, so at some point i may experiment with fuming the oxidized DSP with fine silver to see if the colour lasts longer that way...

Other beads i've made with silver leaf/foil and reduction finishes from the 96 furnace colours, however seem to be ok to date... eg. raku, dark raku, irisgold, iris light blue, etc. beads i made up to 3yrs ago are still fine. I sometimes leave those beads soaking for weeks in tap water with no damage to the finish.

Since that DSP surprised me right in the middle of an order, I have some volunteers who will be doing some wearability tests of certain colours i like to use over the next few months... I've told them to do everything in the beads - shower, swim, sweat, etc. - so i can see how well specific metallic effects/colours hold up.

Since i absolutely love reduction finishes though, I've also decided to seal all my beads with museum wax (e.g. Renaissance) to help prolong the life of the bead surface effects. Plus i added a updated maintenance note on my website for my customers to keep those metallic beads out of water...

RSimmons · #20 2009-09-09, 5:05pm

Quote:

Originally Posted by Firebrand Beads

GADS I love hearing "peer review" instead of "rushing it out" LOL!!!
I will be patient. ;-D

Yes, then plan is for this work to go into a solid scientific journal.

Robert

ewdb · #21 2009-09-17, 9:36am

here's an udpate to my DSP issues (i REALLY like that glass and want to find a way to keep using it) - more highly unscientific testing...LOL.

I took a bead made with DSP shards and polished it according to the directions with Renaissance Wax (that clear museum wax), dropped it in some tap water and left it soaking to see if the colour would disappear. so far we're two+ days and counting and the lovely irridescent gunmetal colour is still stable. every day i take it out, rub it a bit to see if the colour wears off but so far so good.

It'll be soaking for a few weeks at least... if ya'll find this interesting i'll keep posting my results.

Firebrand Beads · #22 2009-09-17, 10:36am

Evelyn! That's great! Thanks for keeping us posted.

FWIW - In a curious moment I grabbed a rod of TAG Cezanne, melted the end into a ball and reduced it in a Dragon's Breath flame - this gave a highly metallic result, what I call a "mylar finish" since you can see through it if you hold it to the light. I then took the cooled, unannealed shiny ball to the sink and scrubbed it *viciously* with a stainless steel pot scrubber. Those are the ones made of metalized ribbons, and they are very abrasive. I did not see much difference at that point; I went into the sun and could still see myself in the shine where I had scrubbed, although it was just barely perceptibly bluer and less silvery there. I have been wearing shiny reduced TAG beads for a while with no noticeable difference in their appearance.

The one glass where I have DEFINITELY lost my finish, however, is a Satake hematite black. That had nice metallic irrids in it on both front and back, but the back part is back to black now. I do not know if this has to do with flame chemistry or not, I will need to go back and test my theories on that glass, too. In my (laff) spare time!

This is a great thread -- what have other folks tried on this front??

glassbead · #23 2009-09-27, 10:09am

This is all great info. I agree, Robert, we do all need to know more about the glass we're using. I use some enamels and really need to get my hands on the MSDS info- I know there's more going on in some cases that just the danger of breathing powered glass. I have never received any info, other than that they are dangerous and you should wear a mask, even when the co. I was purchasing it from said that MSDS would be enclosed.

I wonder, with the metallic questions, if it would wear off differently on different people- like how some folks are highly allergic to different metals. If, for instance, a person had a more, or less, acidic system, might the nature of their sweat influence how things worked? It is a bit alarming to hear about lead content- we have all known that that is terribly bad for a long time, so I really wonder how it can still be allowable. And we certainly don't need to expose children who already have health issues to more poison.

glassbead · #24 2009-09-27, 3:58pm

I just looked through Frit Secrets again, and it is the lead content in furnace glass that makes it compatible with Moretti, etc. But you can make food safe items out of furnace glass! How does that work???

RSimmons · #25 2009-09-28, 2:40pm

Quote:

Originally Posted by glassbead

It is a bit alarming to hear about lead content- we have all known that that is terribly bad for a long time, so I really wonder how it can still be allowable. And we certainly don't need to expose children who already have health issues to more poison.

Surface lead is not allowable now - check out the Consumer Product Safety Improvement Act. It *might* be considered OK if it is inaccessible, but even that is in doubt. Lead on a surface is considered a 'coating' whether it rubs off easily or not - it's mere presence makes it illegal.

Furnace color that contains lead must be encased in non-lead glass to be food safe. You make a gather, roll in color and then gather over it. That encases it, though that won't keep it from getting seriously hot if you put it in a microwave oven. Lead sulfide is still sometimes used in ceramic glazes in other countries and gets blisteringly hot if you nuke it.

Robert

glassbead · #26 2009-10-04, 5:54am

Thanks for the explanation, Robert.

playswithfire104 · #27 2009-10-26, 9:10am

I wanted to post an update to my post #11.

I mentioned that I made a bead with silver glass on the outside and had no issues with the finish wearing off. Well it is wearing off. But again - as I said I do pretty much wear it 24/7. I wore it in the pool and hot tub and while exercising - sweating a lot. I did take it off once in a while to wear something else but I get so many compliments it on I rarely take it off.

debkauz · #28 2009-10-26, 9:21am

Lead makes glass more compatible with each other and it's also my understanding that the higher the lead content of the glass, the more silver it will accept. I am guessing that the high silver content glasses also are high lead. I may be WAY off base here but it's what I remember hearing.

RSimmons · #29 2009-10-26, 9:28am

Lead oxide is used as a fluxing agent in glass. It increases the dispersion of light in the glass ('lead crystal') and tends to make it melt at a lower temp. Addition of lead to high silver content glasses can help with compatibility issues, but not all silver glasses contain lead as many glass makers refuse to use lead these days (I know one personally). Sometimes you'll end up with a beautiful silver glass that's compatible only with itself.

Robert

Robert

Troll Lover · #30 2009-10-26, 9:32am

Is it possible that the high shine of silver glass is also lost if a bead is worn against real silver (925) for a longer period of time?