Min

Playing peekaboo Mark? 🙂

Well I never thought I would be at this for 50 years. It all started with this one show-its turning 50 this weekend in Arcata Ca . It will be my 50 show as well as the shows 50th year (we missed one for covid)
Its been a local event for my whole adult life. I should add a disclaimer that I'm one of the folks who is on the board and helps put the show on. We are called the same old people with lots of meeting budgets etc  over the course of the whole year. I am the only artist left who has done all 50. I have been on a corner for so long  selling pots thats its almost an institution . Now the local paper has a write up by our founder which spells out how the fair started and how it is a total community event (non-profit) Its a good read as Jerry is a great writer. Enjoy the history of this small town festival -Samba Parade on Sunday all speices parade on Saturday Both at 1 pm. Town is 15 k in size and has a town plaza (square) We get a huge turnout and some come from SF about 6 hours south as once you have seen on you always come back.
A Bridge Across the Years: The North Country Fair, 1973-2024
 
At the time of the first North Country Fair there hadn’t been a public event on the Arcata Plaza for three years. In spring of 1970, Henry Kissinger’s bombing of Cambodia had ignited “campus unrest” across the nation. Like now, administrators panicked, cops over-reacted, beat and jailed protestors. At Kent State four students were shot.
            At Humboldt State students brought their protest downtown, where the Kiwanis were having their annual barbecue. Amid the conflict of cultures and generations, a young man started a fire at the entrance of the Bank of America—now the Cal Poly bookstore. (Students had recently torched Isla Vista’s B of A because they were financing bases where bombers re-fueled.)
The fire scorched the bank’s entry, the young man went to jail, and Arcata’s chief of police declared no more public gatherings on the Plaza.
 
So Arcata was already divided when the freeway cut it in half. City Council members—five old white guys—were solidly behind it. So was HSU’s administration. Strange people had moved into town, opened shops that sold strange things. They mingled with students and faculty, became part of the college radio station. Students graduated, but didn’t leave. Started strange businesses of their own. 
These new people were against the freeway and organized to stop it, but it was too late. It was reduced from eight to six lanes, but still the middle of the town disappeared: entire blocks of old houses, a church, a restaurant, trees and gardens, apartments and residence halls. A neighborhood connecting college and town.
Stop at Six had a final meeting. After that bitter defeat, what could they do? One person-she was calling herself River at the time-said: We should give the town a party.
Inspired craziness. Just what we needed. But where?
Now it was 1973. Things were changing. The draft ended. 18-year-olds could vote. The endangered Species Act. Ethnic Studies at the College. Liberals on the City Council. But Chief Gibson’s rule hadn’t changed.
 There was another battle, but this time we won. The first North Country Fair was on the Autumn equinox of 1973. The plaza filled with music, food, crafts and services, businesses and nonprofits, and the townspeople and the students partied and shopped, ate and danced, and saw themselves as one community.
 
The biggest obstacle was again presented by the City: a million-dollar insurance policy and a whopping bill to pay the police to watch us. But eighty booths paid twenty-five dollars each and the Fair broke even, mostly by not paying ourselves anything. And there was this profit: lots of local artists, musicians, services and food places had their beginnings in those twenty-five-dollar booths and on that play-for-nothing stage. 
And there was also this, at the bottom of the mimeograph poster and application form: We believe the basis of our life and economy is cooperation and mutual aid.
Half a century later, the North Country Fair goes on for two days, with two stages, two parades and over two hundred booths. Its budget seems enormous, but it still runs on a shoestring. Crafts people and artisans and nonprofits still struggle to stay solvent. Musicians play for a small honorarium. This year there will be a chance for fairgoers to help pay the bands and keep the music going. Please contribute what you can.
 
Yet all these years later, the freeway and the college administration are still a divisive issue.
Caltrans has offered to atone for some of its massive ecological and social damage— $148 million divided with San Diego and San Francisco to compensate for engineered apartheid. Arcata’s share will be small, but there is already a plan for more engineering—The Arcata Cap-to put five-acres of reinforced concrete over Highway 101, from 14th to 17thStreets.
But the administrators and trustees of the State University, on the other hand, are still using every means possible to isolate itself from the town—and from its own faculty and students. There is far more interest in power than education. More than ever we need a college that is not afraid of the town, and a town that doesn’t try to fix all its problems with cement.
I call upon all of us, students and townspeople, to recognize and
 celebrate the spirit of the North Country Fair. Please join us on the Plaza on September 21 and 22. Happy Equinox,
                                                                        Jerry Martien
                                                                        Director Emeritus 
The North Country Fair 

ha, well, I wouldn't call it patience, I wrote off getting them long ago. If I get them it would be nice though. Frankly, I became more intrigued by all the mythology and internet theories that came about. 

Chrome is volatile, it will flash too. Think of a white glaze opacified with tin, if you have a glaze containing chrome near it while firing the white can flash pink from the chrome.

You have been very patient Morgan, I really hope you get your order soon.
 

If the solution is to add gum then I would make as concentrated a solution as possible to add to reduce the amount the underglaze is diluted as much as possible.

Does the underglaze smell at all? Thinking the gum(s) are breaking down.

Does the underglaze smell at all? Thinking the gum(s) are breaking down.

Does the underglaze smell at all? Thinking the gum(s) are breaking down.

It's flashing from the super high amount of sodium in the glaze. (and probably the cause of the crazing too)

I prefer to use the term "durable" rather than food safe when talking about glazes. There isn't one agreed upon definition of what makes a glaze "food safe". In North America if a glaze does not contain lead or cadmium it can be labelled food safe. This is a very wide definition and adding something along the lines of what Mayco says "Finishedware producers bear responsibility for food safe testing their ware being sold into commerce." IMHO isn't good enough. Like Callie said Strontium Crystal Magic (SCM) is  fine on the outside of pots where your mouth or food won't be in contact with it.
Re lithium and toxicity, just adding a little bit. Topic of lithium and toxicity has come up in many discussions in many forums etc over the years. My impression of the reading I've done is it might not be an issue for most people but for those on lithium therapy it can be, both in the process of mixing glazes and leaching glazes.  Poison is in the dosage scenario.
With all due respect to Callie I found SCM quite rough, dry and unmelted. You could try it by itself on a test tile and see how you find it but it's a bit of a moot point because it isn't used by itself.  The overload of titanium is what makes the crystals/variegation when layered with other glazes. A good way to get interesting glaze reactions is to layer 2 or more dissimilar glazes, what one glaze lacks or has a surplus of reacts with the other glaze, this often results in interesting visual texture. SCM is loaded with fluxes to react with other glazes, that's part of the reason why it works.
Re silica and glaze durability, having as much silica and alumina in a glaze is one of the ways to ensure a durable glaze.  For cone 6 having at least 2.5 molar of silica is a good starting place, if the glaze can dissolve more then it's a good idea to add it if you are looking for a durable glaze. If you look at the screenshot above in the bottom half of the image you can see the silica is 1.68 so at the bare minimum it is about 1/3 short of where it should be. Overloading a matte glaze can quite often turn it into a gloss glaze  and really oversupplying it can turn it back into a matte and crazed glaze so there are parameters within which to work. 
Another aspect of silica that is often overlooked is the mesh size of the silica being used. When you mix glazes using a 325 mesh size silica more of the silica will likely be dissolved in the glaze than if you use 200 mesh. (not applicable for the SCM)
One more thing is to look at the colouring oxides used. Don't use crazy amounts of colouring/transition oxides, use the least you can to still achieve the effect/colour you are after.
There is a good article on toxicity that includes materials here if it helps.

It's flashing from the super high amount of sodium in the glaze. (and probably the cause of the crazing too)

@Min  @Callie Beller Diesel 
First and foremost, I want to apologize for my delayed response! I want to thank you both for such an in-depth response on toxicity. What you both said makes sense. I appreciate your time on sharing this information. 
 
Best regards, 
Caroline

I prefer to use the term "durable" rather than food safe when talking about glazes. There isn't one agreed upon definition of what makes a glaze "food safe". In North America if a glaze does not contain lead or cadmium it can be labelled food safe. This is a very wide definition and adding something along the lines of what Mayco says "Finishedware producers bear responsibility for food safe testing their ware being sold into commerce." IMHO isn't good enough. Like Callie said Strontium Crystal Magic (SCM) is  fine on the outside of pots where your mouth or food won't be in contact with it.
Re lithium and toxicity, just adding a little bit. Topic of lithium and toxicity has come up in many discussions in many forums etc over the years. My impression of the reading I've done is it might not be an issue for most people but for those on lithium therapy it can be, both in the process of mixing glazes and leaching glazes.  Poison is in the dosage scenario.
With all due respect to Callie I found SCM quite rough, dry and unmelted. You could try it by itself on a test tile and see how you find it but it's a bit of a moot point because it isn't used by itself.  The overload of titanium is what makes the crystals/variegation when layered with other glazes. A good way to get interesting glaze reactions is to layer 2 or more dissimilar glazes, what one glaze lacks or has a surplus of reacts with the other glaze, this often results in interesting visual texture. SCM is loaded with fluxes to react with other glazes, that's part of the reason why it works.
Re silica and glaze durability, having as much silica and alumina in a glaze is one of the ways to ensure a durable glaze.  For cone 6 having at least 2.5 molar of silica is a good starting place, if the glaze can dissolve more then it's a good idea to add it if you are looking for a durable glaze. If you look at the screenshot above in the bottom half of the image you can see the silica is 1.68 so at the bare minimum it is about 1/3 short of where it should be. Overloading a matte glaze can quite often turn it into a gloss glaze  and really oversupplying it can turn it back into a matte and crazed glaze so there are parameters within which to work. 
Another aspect of silica that is often overlooked is the mesh size of the silica being used. When you mix glazes using a 325 mesh size silica more of the silica will likely be dissolved in the glaze than if you use 200 mesh. (not applicable for the SCM)
One more thing is to look at the colouring oxides used. Don't use crazy amounts of colouring/transition oxides, use the least you can to still achieve the effect/colour you are after.
There is a good article on toxicity that includes materials here if it helps.

If we have a look at the recipe and formula mentioned in the thread above there are some alterations to make to the glaze to get it to melt at cone 6.(info from that thread at the bottom of this post) Either boron (from a frit or Gerstley Borate) or zinc will be needed to flux it enough for midrange.
For boron the obvious choice would be Ferro Frit 3269 as its a boron frit with very low calcium with no other alkaline earths but it also contains zinc. However, it is very high in sodium,( Na2O), and potassium, (K2O), which is likely to increase glaze crazing from their high Coefficient of Expansion (COE). So to adjust the glaze to reduce the COE there must be either Lithium added at the expense of some of the K2O / Na2O or one of the low COE alkaline earths, magnesium, (MgO), would be a good choice. Problem with this is then you are back to alkaline earths washing out the iron, albeit less so with MgO than CaO.
Second problem to address is the colour response zinc can cause with iron. Granted there isn't a great deal of it with Ferro 3269 so this might or might not be an issue if you can come up with a formula using it with lithium to counteract the high COE plus increase the Al2O3 and SiO2 would be necessary to make a workable midrange glaze. Might be somewhere to start if you want a deep dive into glaze chem and testing.

 
44% North Cape nepheline syenite
34% Potash felspar
20% AB clay
2%  Kaolin
... which is attempting to achieve
0.8 K2O
0.2 Na2O
1.17 Al2O3
0.05 Fe2O3
5.35 SiO2
edit: for the purposes of this discussion I have left the flux ratio out of the equation but it should be considered.

Hi Alan and welcome to the forum.
Iron tends to get bleached out by the calcium that is found in most cone 6 glazes. I don't know what is available on your side of the pond but you might want to look at using either a brown underglaze, or a brown and black mix of underglazes, or a ceramic stain mixed with a frit to help it adhere to the pot plus some kaolin.

Yes.

well, the kiln at the community studio was fired by a few others, not me.  And there weren't any nuances, simply push start and go. 
I was fortunate enough to buy a brand new L&L in 2012.  It has a great instruction manual, plus phone and email support.  When we were getting the kiln set up, the electrical inspector insisted that we hardwire the kiln, rather than plug it in.  I emailed L&L to see if that was usual and Stephen Lewecki called me.  He is the president of L&L.  (I love this company!)   So, how did I learn to fire my kiln?  On the shoulders of others and lots of trial and error.  12 years later, I have almost 1000 firings on this kiln, my husband and I now know how to replace elements, bricks, channels, thermocouples, harnesses, wires.  I can, with the help of the manual, program Vary Fire programs.  I help out with the kilns at the community college.  So doing equates to learning!

By reading the owners manual.
By reading a Duncan service manual. It's an older manual, but still a good reference. It has some good safety checks. https://eadn-wc04-7751283.nxedge.io/wp-content/uploads/LX_809_Duncan_Kiln_Service_Manual-1.pdf
By firing my own electric kiln. By building my own gas kiln conversion and firing it. By just diving in and doing maintenance on other people's kilns. It doesn't hurt that I have a background in electronics and electrical work.

Good one Min... you'd think getting folks to throw wood in the kiln would be simple.  BUT NO!!! Although having lots of good food helps alot.

Yes.

Yes.

It’s fine to write out glaze or wash, slip, claybody etc recipes  @Babs

Huh, I always thought you fired with wood. (my bad but couldn’t help it)

It’s fine to write out glaze or wash, slip, claybody etc recipes  @Babs