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Rich Samuel 04-17-2019 02:26 PM

In the late '70s, I worked for Water Pik. We introduced a faucet-mounted water purifier called InstaPure (now, spun off as a separate company). The Feds made us recall them because the filters contained trace amounts of silver, considered highly toxic.

It looks like science finally prevailed, though:

Too much exposure will, however, make you eligible to join Blue Man Group. ;)

Pete VanderLaan 04-17-2019 03:39 PM

It also says this, which I view as a high level exposure if you are vaporizing a metal:
" In factory environments where high exposures to silver dust or fumes are likely, protective clothing, gloves, eye goggles and ventilators or respirator equipment can prevent ill effects."

What's an ill effect. STEL limits are on all materials and that's the level beyond which, bad things happen. Given the value of silver, it's likely that no one is interested in blowing it off into the atmosphere. I would still say any material reduced to nanoparticles is worth giving the evil eye.

Larry Cazes 04-17-2019 10:21 PM


Originally Posted by Don Geiger (Post 143748)

First and foremost thank you for your response.

Is this the DVD you were thinking of, Flamework: An Intimate Art? If yes, and you are looking for a replacement copy it is available at

Two fuming questions.

1) Is fumed glassware safe to use with consumables like beverages and food?
2) Do you encase your fumed work?

Thank you once again.



Yes. Thats it. Im inclined to hunt down and retrieve my copy that went astray :) Thanks.

Everything that I fume is eventually fully encased in clear. I am making large solid spheres with three dimensional landscapes inside that are created by fuming Gold and Silver onto Borosilicate clear.

When I first started down this path I did extensive research concerning the toxicity of these metals and was not able to confirm any but I also believe in doing what I can to minimize my exposure to them. I ALWAYS work underneath an overhead hood with an appropriately sized exhaust fan. It just seems like good practice to me.

Don Geiger 04-18-2019 07:02 PM

Thank you

Originally Posted by Pete VanderLaan (Post 143754)
Chemical approach to Glass by Milos Volf is what you want. I also have technical glasses by Volf but I don't think it's remotely going to help. Igneous Glass in Utah reprinted the Volf. It shows up in a google search. It won't get another printing so, when it's gone, it will be gone. The original from 1980 runs well over $1,000 dollars. Obscure science.


Many thanks as always.

I've found a few volumes in fair quality for ~$350. My concern is which language they are published in. All of that aside, Thank You for introducing me to a new recommended source of information.

My only real concern here is having to put off a computer upgrade, spend my mad money beyond my budget. I'll stress test my current system this weekend. If it passes I am buying this book. Come on stress test. ;-)

Thank you, without your help I'd never have found this tome.

Oh heck yea, please publish! Just let us know when it is available and where. In very plain English, as I learn my way around here, gleefully saving ideas, you sir are a veritable fount of wisdom (IMHO).

Once again and as always many thanks.



Don Geiger 04-18-2019 07:35 PM

Thank you and Silver has some safety issues

Originally Posted by Sky Campbell (Post 143760)
I can say from my knowledge there is no toxicity related to silver or gold. Fairly safe to fume with and no toxicity problems with using a vessel fumed with either metal.

That said fuming silver and gold doesnt work on soda lime the way it does on borosilicate. Im not going to get into why that is maybe someone else will elaborate.

Dear Larry and Sky,

Thank you both for your time and shared wisdom.

Based on your guidance I plan on fuming with both.

If I may be so bold I am going to contribute to the oft, based on posts here, disputed safety of gold and silver. Disclaimer - my information is old but recently updated specific to medical applications of Silver.

The easy one first. They used to inject Gold to treat arthritis. It is also used in dental work. More or less it is biologically inert. Then again what I was exposed to was safe at the time. Just saying.

Silver is another matter. Do your own search of MSDS for providers and make up your own minds. It is used to swab new born's eyes to protect them from possible microbiological contaminants from the birth channel. It is again used topically to protect burn patients from infections when their skin is burned off. It is used, myself included, to inhibit algae growth in custom water cooled computer systems. It kills stuff, preferably not me or you.

Gold and Silver fuming does not scare me. Let me try it this way. After a life time of training to be a dirty old man I find myself about to be there. Ventilation is very important to me; not just for fuming but for merely fiddle pharting around with glass on a torch.

The rule of thumb I found was to spend no less on a ventilation system than on a torch. Back in the day before certain things were classified as carcinogenic I got zonked out of my mind on fumes cleaning optics from what is not classified as carcinogenic. I don't care how safe it is supposed to be. I am not about to break decades of training to be a dirty old man for want of a proper ventilation system; ever.

Please understand I am not trying to stir any pots here. I shared why this is MHO. I provided facts that can be verified about Gold and Silver. The conclusion is ventilation is important and if you are also in training to be a dirty old man or woman ignore ventilation at your own peril! Since I want to be around long enough to be an embarrassment to both the kids and grand-kids good ventilation is a no brainer for me.



Don Geiger 04-18-2019 07:48 PM

Tkank you as always and a follow up question.

Originally Posted by Larry Cazes (Post 143785)
Yes. Thats it. Im inclined to hunt down and retrieve my copy that went astray :) Thanks.

Everything that I fume is eventually fully encased in clear. I am making large solid spheres with three dimensional landscapes inside that are created by fuming Gold and Silver onto Borosilicate clear.

When I first started down this path I did extensive research concerning the toxicity of these metals and was not able to confirm any but I also believe in doing what I can to minimize my exposure to them. I ALWAYS work underneath an overhead hood with an appropriately sized exhaust fan. It just seems like good practice to me.


Thank you as always. I am happy that I actually in some small way provided something you are interested in.

I've become lost between which thread I read what in where. Somewhere you shared what you make when fuming. I have yet to find it.

I'd very much like to see some examples. If you could share a link or few it would be appreciated. I just cannot envision what you described.

As always many thanks.



Don Geiger 04-18-2019 08:13 PM

Thank you and a few follow up questions please

Originally Posted by Bradley Howes (Post 143761)
please pardon the lack of capitalization in this post, my shift key gave out.

Recently in my Glass Art Engine independent study at AU, I've been able to make gold ruby glasses with some success. Starting with 100g of spruce pine color base, i add .2g of black tin oxide and 1ml of dissolved gold. this gold solution has a fixed amount of gold per ml, this amount is known quantitatively. the ingredients are mixed thoroughly and then melted in an electric furnace at 1400c or 2552f. this will strike to ruby after 4 ish hours at 600-650c. when i mix 100g spruce pine with .4g black tin and 5ml, the gold strikes immediately when i pour it out of the crucible into a small graphite mold. i've also mixed an opaline gold as follows;
100g spruce pine color base
5ml gold solution aka .05g of gold
.4g black tin ox
4g stpp
1g potassium nitrate
1g boric acid

the tin helps with the solubility of gold to promote striking in the low temp range. the stpp is for opalescence. the potassium nitrate is being used as an oxidizer to keep the gold from forming metallic beads on the surface of the melt, this was a problem in an earlier melt. the boric acid was added just to balance things out a little. jacob willcox uses it in his melts to help with melting and compatibility. the two images included are lip trimmings from a vessel i made with the gold opaline.


Thank you for sharing this and your following posts.

My goal / plan is to use the wisdom shared here and elsewhere to mix colors in borosilicate at torch. Being new here where I posted what where is lost; a url for the techniques was posted somewhere here and I can provide it again if needful.

If I missed it here please forgive me I am a noob and rather overwhelmed by the fecundity of information. In addition to your posted formula that did not use Selenium (Sp?) What mixed with what creates what is of special interest. Anything you would be willing to post here or URLs would be appreciated.

Thank you in advance for any light you can shed on my research.


PS: this was the first time I've ever read about Spruce Pine Color Base. Searching on-line provided unsatisfactory results so additional research leads would be appreciated.

Jordan Kube 04-18-2019 11:35 PM

Bravo Bradley!

Pete VanderLaan 04-19-2019 08:11 AM

To the best of my recollection, Spruce Pine color base was an outgrowth of my first color class held in Santa Fe. Tom took that class. I had asked him to provide me with the SP87 formula without the additives of nitrates or antimony which are fining agents for the clear glass. Colors in reduction really need to have oxygen excluded from them wherever possible. Tom did that and we took that material and took shots at making copper ruby from it and hit it on the first try. It was not a great copper ruby but my take on the color was that it really needed a very pure calcium and that was not in that mix. If I was doing that color, I would use a food grade hydrate lime. I recall talking with Dick Ritter about that some years later.

So, Tom began to sell that product, unadvertised of course which seems the way of Spruce Pine. Half the world doesn't know he mixes Gaffer's formula for sale, sells Gaffer color rod ( no frits) and mixes snowflake variants of all batches.
The SP color base is not mixed, it's just the raw chemicals in the bag, You have to mix yourself.

I don't know how many copies of Volf actually remain for sale. I think Joe was disappointed in the response to it and I don't think it will get reprinted. Another mayfly book in Glass.

Greg Vriethoff 04-19-2019 01:54 PM

The Volf book is something I have had on my want list since Joe began selling the reprint. $200 is a lot for someone that makes less than 20K annual income. I had a brief exchange with Joe, and he said he would be willing to work a trade for some glass to lower the price. I don't know how much he pays attention to this now since there's no longer any interest like Pete says. It's such an esoteric subject I'm not surprised.

When I was a grad student in SoCal (2003-2007) my wife was also working on her PhD at UCLA. The engineering dept had a copy that had last been checked out in 1994. She had very generous library privileges, and could check out up to 200 or so items at a time. She only had to return items if someone else requested them. I had that original copy for five or six years. I had to give it back when she graduated in 2010. Bad on me for never making scans/copies. It really wasn't serving me very well since I was not actually getting into batching my own glass. It's very dense, and I'm not a chemist.

Pete VanderLaan 04-19-2019 06:34 PM

The marvel to me about Volf is comparatively, it's not dense, not like Weyl.

Oh well, Hodkins and Cousins had last been checked out of the State of New Mexico Library in 1936 when my teachers expropriated it.

Those pages on making copper ruby are just filthy with copper oxide smears.

I would tell anyone seriously interested in the subject to borrow the money to buy it now. I never would have thought Glassnotes IV would bring $600 dollars let alone see Volf in a recent reprint for those kinds of prices. I haven't seen any copies of the Wilhelm Schmidt translation by Lyngaard available it all. Coloured glasses as the hardbound, I have no notion of value. I haven't seen it on the market in ten years. Softcover, that POS reprint on toilet paper is one I had once, I don't know where it falls in.

Think of Mayflies people. Two weeks and they're simply gone. We have a history of this. These books are definitely not forever.

Rich Samuel 04-20-2019 01:24 AM

Could it be a tough sell at $200 a pop because there are copies available in 117 academic libraries in the US and Canada?

Pete VanderLaan 04-20-2019 09:27 AM

Anyone serious about the chemistry of glass would want to own this and Weyl. Currently, it sells for more than the original asking price. There's a reason for that. It's true of Glassnotes IV as well. I would certainly never sell any of my glass books after fifty years of glass.

Jordan Kube 04-20-2019 03:09 PM

I've been thinking about picking up where Glass Notes left off. There's nothing else like it out there but people are still hungry for the information.

Pete VanderLaan 04-20-2019 04:08 PM

The question is how to pick it up. Since I wrote the section on batch, that world has entirely changed. The suppliers are pretty much gone, many materials simply are no longer available.

Building your own equipment seems distant now compared to 1990. There's little desire and perhaps even less confidence and Henry laid that put quite well.

Something I get to do is to look at the sites where the lurkers are hanging out and it's never in the current material. I find them in really strange places.

I asked my son last night to secure the data for the entire period and he is willing to do that. It's an enormous amount of stuff. The book could just as easily be organizing all those observations into something one could write an index for. Collating that 120 thousand posts would take more than a year working full time. Katie continues to hold copyright and has yet to let go of the show although she sees that writing on the wall.

Principally, Henry has all the material from the book but what to do with it. I do firmly believe it needs to be in print form. I can put up the money to print but I indeed need help and you are one of the people I was going to inquire with. The fact that the used copies sell for over five hundred dollars tells me you're right about the need for information.

Most of the pioneers are at the end of the trail now. All I have to do is look around and watch the herd being culled. There's a phenomenal amount of knowledge there. I don't think any of us writing then felt we had exhausted our material. Certainly Frank and I didn't but the question remains as to how to keep after it. I thought Greg to be accurate when he said students didn't want to question, they just wanted answers. I'd prefer roadmaps.

Boro needs real treatment and I'm not qualified there at all. I see it as being unpublished to date. This site doesn't reflect the good work being done on that. That being said, I'm still disappointed that I think we are far dumber as a group than we were in 1990. That shouldn't be.

Jordan Kube 04-20-2019 04:46 PM

There's a lot of ways to approach it thanks to the internet and the tools that are available now. It's possible to transmit much more information and in more detail than a book. Print still has a place though, it's not black and white. I'm almost done with my OpenLathe project, where I take people through the steps to build their own glass lathe. Almost 2 hours of video at this point I think. It's free for anyone now but I chose to fund the creation through Kickstarter. How to build a forge or metal foundry furnace are a dime a dozen on YouTube but a lot of it is garbage or they don't have plans and other details. I feel like there is room for well done plans and walk-throughs with good information for all kinds of equipment but it's going to cost people money. Not much money but it won't be free.

Pete VanderLaan 04-20-2019 06:49 PM

It's not my element. I think you will do fine.

Don Geiger 04-21-2019 01:52 PM

Yes, there is a lot of interest.

Originally Posted by Jordan Kube (Post 143812)
I've been thinking about picking up where Glass Notes left off. There's nothing else like it out there but people are still hungry for the information.


You are 100% correct, there is a great deal of interest. As you point out in a later post there is also a lot of bad information. I'd never have discovered Chemical Approach to Glass if it were not for the people here. Heck, the Rakow library recommended the pipe making community as a source of information about coloring boro glass. No joy, but I looked.

Jordon and Pete,

1) What is wrong with PDF based publications? (depending on how I use the information I print them out, otherwise they are saved or discarded) It reduces the cost of publication.
2) Kick start funding is viable with a caveat. People have to know it is out there. What better community to accomplish that than this one?
2a) Preservation of the wealth of knowledge here. I am trying to read everything about coloring glass here and an Index to find things sounds like a winning way to publish everything.
2b) Glassblowing - I cannot do $500 but that price and the ongoing scarcity is not justified by being out of print. I suggest it is because, with out dated things like vendors and all, there is a demand for the information it contains.
2c) Jordon, based on your posts here I'd buy your book in a heart beat!
3) I look at kick starting this way, I want the books so I'd spend what I can afford via a kick starter for them. PDF or hard copy is not an issue as either way I'll be able to read them. :-)
4) Please publish!


Please share the links for your glass lathe. Mister Drier's (Sp?) and Goldschmidt's work with large diameter boro tube should be adaptable to and the improved temperature control I've witnessed are a winning combination.

CMOG has YouTube videos of both their work. Salem's Glass Master's Series has someone, the name eludes me, making drinking vessels on a glass lathe.

Soap box just creaked so I'll shut up now.



Pete VanderLaan 04-23-2019 12:05 PM

Scarcity of Glassnotes IV does drive the price. Sometimes it's irrational. Most schools should have it in the library but I'd advise against leaving your personal copy around.

I sold a comic book last year for over 50K. It's actually not rare. It's just something that everyone in that world wanted and they have a heartfelt belief that it's a good investment. It has actually gone down some since I sold mine in Dubai of all places. Amazing Fantasy 15, the introduction of Spiderman.
I think there are about 400 copies in better shape than mine was in and about 500 that are the same. Really nice copies go for 800K and more. The estimate are that there are probably another 1,000 out in the wild. Nothing similar vaguely commands the price.

As glassnotes becomes harder and harder to find, and I do think that to be true, it will be an interesting question as to why folks want it. I think that to be true of Volf more so because there just aren't very many of us who care about the chemistry. People do strange stuff. I keep reading my copy and melting glasses. .

Jordan Kube 04-23-2019 02:10 PM


Originally Posted by Pete VanderLaan (Post 143848)
I think that to be true of Volf more so because there just aren't very many of us who care about the chemistry.

I don't know Pete. I was told John Croucher's class had the longest wait list in school history. People are out there that want the info, they just don't know they need that book!

Pete VanderLaan 04-23-2019 02:39 PM

In retrospect, I wish I had taken John's class. Those of us at 70 aren't going to be around that long. John, given gaffer, carries an extra amount of weight.
How was it? He had told me he was going after some copper ruby for casting.
The trouble there is how much Penland pays and it really offers no incentive to teach that way. It was why I turned it down and opted for doing it in my own studio. Joe didn't print that many copies but they were slow to sell.

Bradley Howes 07-11-2019 12:35 PM


Originally Posted by Pete VanderLaan (Post 143768)
Bradley: That's very cool that you are able to do that with the SP color base. Given that you're adding the nitrates to your stuff, I doubt you really need the base. Conventionally, rubies made in a non lead base are far weaker in intensity than those made in a lead. Further, it's unusual to see rubies made without a trace of Selenium. You might try adding it. That's great work and I appreciate your thoroughness. What kinds of effects is this having on expansion.


Lately I've been doing the following for my gold ruby:
100g Spruce pine color base
2mL Au solution aka .02g
.2g SnO
.5g KNO3
.01g Se metal, crushed (grey allotrope)
The gold solution gets added to the SPCB first and mixed, there's a little acid left over and I just want to avoid any possible weird reactions/changes in valence of the other ingredients. Then I mix in all the other ingredients except the selenium. This mix gets run through a 40 mesh sieve. I previously used 60 mesh but it would take me forever to sieve the mix, I haven't noticed any difference from using the 40. After the sieve, I put a lid on my container and give it a shake. Finally, I take about 3-5g of the mix and mix the selenium into it. This selenium mix gets put into the bottom of my assay crucible and then all the rest of the mix goes on top. My thinking with this is as the selenium volatilizes, it passes through all the batch above it (up is the only way out). This is melted for 1 hr at 1350C 1C (2462F). When I pour this into a graphite mold about 1" diameter, 1-3/4" tall, it starts off clear but strikes to a DEEP red before it loses all its thermal glow. Out of the annealer, the puck looks black until I shine my flashlight through. Even then though, I can barely see my flashlight but it has a perfect ruby color.
My only issue with this is I get some brownish reflections. I think this is Type VII deposition of the tin (see Wyel's page with the flowchart of gold crystallization).
I've taken some of these pucks and used about 3/5ths of them (~50g) in the hotshop. The color makes for a small overlay but when blown out into a medium sized cup, it has some density to spare. Amazing ruby color but those browns still show up when light reflects off the surface, looking through, they disappear.
Finally, I've also tried modifying the color. I of course have the opaline from earlier in the year (I think I'll revisit this once I've sussed out the brown reflection). I've also mixed in .15 and .1% cobalt for amethyst (super expensive off brand manganese purple, nearly a dead ringer) and a redder version of amethyst. Also, I tried for burgundy with cobalt and nickel, I only did one test of this before I left AU for summer and I think I need more of both oxides.

Pete VanderLaan 07-11-2019 02:49 PM

You don't say how you are firing it. Gas or electric? The brown is some really big molecules reflecting light back at you. You might consider backing off on the gold by about 20% and see what the strike does then. Just save all the tests and they can be combined into more tests later.

I'm not at my formula sheets right now but I recall having 2 grams of gold in about 25 lbs of batch. John C always told me I didn't need the tin really. The selenium you really do need. Your formulation might do better if you procured some lead carbonate and added a bit to the mix.
The sieving issue won't make a lot of difference at the temps you melt at from which I really should infer it's a gas furnace. The materials in it are pretty much all prilled now which reduces dust. I dislike it in potassium and sodium nitrates and I grind it up in a coffee grinder when I'm doing sensitive mixes. I occasionally wonder if doing that will cause an explosion. Then I shrug and do it again.

Bradley Howes 07-11-2019 06:35 PM

The furnace I'm using is a Carbolite Gero, it's an electric furnace commonly used by glass engineers. It has a max temp of ~1600C. For my tests, I store each glass puck in the crucible it was poured from, each crucible is then stored in an empty crucible box in chronological order. I have a video of it on my instagram @bradleyhowes.gae (I'd love to hear your thoughts if you take a look at the page). You should be able to view it without needing an account. I have pretty much every single test I've melted on there.
Looking at your 2g/25lbs, that comes to ~.0176%, your suggestion to knock off 20% puts me at .016%. I've done a couple melts without tin, one such was .02% gold, .005-.01% selenium, and .5 KNO3. The strike was pretty streaky, about half the sample was clear, the rest was poorly struck 'ruby cords' if you will. I understand from Wyel and Volf the tin can be skipped if the glass has lead, how much, I don't know. How much lead carbonate do you think I should add? I think this starts to tie into my other thread about lead crystal now...
My big concern is when I take the gold ruby out of the lab and into the studio. The exp. furnace we have freaks out if you set the temp at 2300F. I haven't had any issues at 2275F so far. It's slightly reducing as well, great for my calcedony. I wonder if between temp and atmosphere if I won't be able to melt gold. My best idea so far is to take my test crucibles and add some gold batch and toss that into the furnace next time I charge. I figure that'd get as close to real world as possible with out being 25-50lbs of glass. I can explain that better if it doesn't make sense.

Pete VanderLaan 07-12-2019 07:21 AM

surface area in the pot matters and a small pot has a very high one so shape of the pot becomes important. The conventional wisdom says that the top 1/2 inch of the melt is affected by the atmospheric condition and everything else is localized so a big surface area will throw your results some. I always did those melts at 2300F and they were gas fired back in Santa Fe. The ones we did here for the classes were all gas.

I understand the streaking issue. The lead would really help. Start small. 10 grams but increase the nitrate by .5 gram to perhaps stir it a bit better.. Univ pigment sells the carbonate, it's just pricey. Doing it in electric is harder. watch your PM's. I'll try to send you something.

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