[dorie]

Hi,
Im somewhat new to Crystalline glazes and wonder, is anyone using crystallines or have you in the past,?
I've had some very fun results lately and can't always explain the why. I'm reading and researching every day, firing at least weekly... and find them just facinating.
Thanks, Dorie

[Marcia Selsor]

I did my MFA thesis on crystalline glazes back in 1973. I found them fascinating as well. But after a while I moved on to other fascinating things. I did a lot of research in the basement of the ceramic engineering building library at UI in Champaign Urbana. There had been a lot of research on crystalline glazes around the early 20th century there. I found recipes and firing schedules and descriptions of shapes of crystals. I also discovered Adelaide Robineau and found interviews with her in Ladies Home Journal from 1915 in UI library. That was fun research too.
I had an interesting visit with a collector in Chicago who had some pieces in her collection that had curly-cue form formed crystals by a famous pottery couple. I'll remember their names tomorrow maybe. It was a husband and wife team who taught Beatrice Wood. I have a book about them, but I am on the road at the moment.
I experimented with the firing schedule as well as colors from some rare earths that I got from the chemistry department. They are fun and mesmerizing.

Marcia

[dorie]

Marcia,
I love your work and had no idea it also includes experience & research with crystalline glazes. Amamzing!
In my next cone 9.5 firing this wk, I am attempting for the 1st time to grow halos. But I am frustrated by too many crystals. Although beautiful, they are stacked on top of one another and I have very little background color. Trying for more background, I am planning to decreasing the zinx oxide by 1% in my base glaze. What is your opinion on that?
And do you have any suggestions concerning halos? I was guessing in my 4 hr. hold @2050, I'd ramp up & down the temp 4 times/1 hr each.
This firing I am attempting to change 2 variables; holding schedule & less zinc ox. Any thoughts? Thanks, Dorie

[Marcia Selsor]

dorie, on 20 December 2010 - 04:18 PM, said:

Marcia,
I love your work and had no idea it also includes experience & research with crystalline glazes. Amamzing!
In my next cone 9.5 firing this wk, I am attempting for the 1st time to grow halos. But I am frustrated by too many crystals. Although beautiful, they are stacked on top of one another and I have very little background color. Trying for more background, I am planning to decreasing the zinx oxide by 1% in my base glaze. What is your opinion on that?
And do you have any suggestions concerning halos? I was guessing in my 4 hr. hold @2050, I'd ramp up & down the temp 4 times/1 hr each.
This firing I am attempting to change 2 variables; holding schedule & less zinc ox. Any thoughts? Thanks, Dorie

You can change the shape by adjusting the holding temperature at a different range. I can check my schedules. I grew halos or rings some with many rings. I can send you info whenI get home at the end of December. The potters I mentioned were Gertrude and Otto Natzler. Check out their work. Beautiful crystals.
Marcia

[Marcia Selsor]

Marcia Selsor, on 20 December 2010 - 08:16 PM, said:

dorie, on 20 December 2010 - 04:18 PM, said:

Marcia,
I love your work and had no idea it also includes experience & research with crystalline glazes. Amamzing!
In my next cone 9.5 firing this wk, I am attempting for the 1st time to grow halos. But I am frustrated by too many crystals. Although beautiful, they are stacked on top of one another and I have very little background color. Trying for more background, I am planning to decreasing the zinx oxide by 1% in my base glaze. What is your opinion on that?
And do you have any suggestions concerning halos? I was guessing in my 4 hr. hold @2050, I'd ramp up & down the temp 4 times/1 hr each.
This firing I am attempting to change 2 variables; holding schedule & less zinc ox. Any thoughts? Thanks, Dorie

You can change the shape by adjusting the holding temperature at a different range. I can check my schedules. I grew halos or rings some with many rings. I can send you info whenI get home at the end of December. The potters I mentioned were Gertrude and Otto Natzler. Check out their work. Beautiful crystals.
Marcia

I googled them but didn't see any crystalline glazes like ones in their book.

Bookseller Image

View Larger Image

Form and Fire: Natzler Ceramics, 1939-1972

Natzler, Otto; Joshua C. Taylor (Foreword); Lloyd E. Herman (Introduction); Daniel Rhodes (essay)


Description:
120 pages; an exhibition at the Renwick Gallery of 175 pieces described, about half are illustrated, most in full-page color. Many pieces include in their desciptions annotations by Otto Natzler who comments on Gertrud's throwing and on his glaze. Gertrud died in 1971 but left many bisque-fired pots to be glazed. Includes list of lenders, biographical notes, bibliography, two photos of the Natzlers, including frontispiece. Previous owner's name, otherwise clean throughout, pages crisp; covers only lightly shelf-rubbed, two light creases at the bottom corners. See image. Bookseller Inventory # 003644

Description from Abe's Books.com

[Avi]

dorie, on 20 December 2010 - 02:18 PM, said:

Marcia,
I love your work and had no idea it also includes experience & research with crystalline glazes. Amamzing!
In my next cone 9.5 firing this wk, I am attempting for the 1st time to grow halos. But I am frustrated by too many crystals. Although beautiful, they are stacked on top of one another and I have very little background color. Trying for more background, I am planning to decreasing the zinx oxide by 1% in my base glaze. What is your opinion on that?
And do you have any suggestions concerning halos? I was guessing in my 4 hr. hold @2050, I'd ramp up & down the temp 4 times/1 hr each.
This firing I am attempting to change 2 variables; holding schedule & less zinc ox. Any thoughts? Thanks, Dorie

Try going up and down 2050 > 1900 > 2000 > 1850 > 2000

Try going down 1% zinc and up 1% silica

Read:


Macro-Crystalline Glazes: The Challenge of Crystals by Peter Ilsley


http://www.amazon.co...92899897&sr=1-2

[Marcia Selsor]

Marcia Selsor, on 20 December 2010 - 08:24 PM, said:

Marcia Selsor, on 20 December 2010 - 08:16 PM, said:

dorie, on 20 December 2010 - 04:18 PM, said:

Marcia,
I love your work and had no idea it also includes experience & research with crystalline glazes. Amamzing!
In my next cone 9.5 firing this wk, I am attempting for the 1st time to grow halos. But I am frustrated by too many crystals. Although beautiful, they are stacked on top of one another and I have very little background color. Trying for more background, I am planning to decreasing the zinx oxide by 1% in my base glaze. What is your opinion on that?
And do you have any suggestions concerning halos? I was guessing in my 4 hr. hold @2050, I'd ramp up & down the temp 4 times/1 hr each.
This firing I am attempting to change 2 variables; holding schedule & less zinc ox. Any thoughts? Thanks, Dorie

You can change the shape by adjusting the holding temperature at a different range. I can check my schedules. I grew halos or rings some with many rings. I can send you info whenI get home at the end of December. The potters I mentioned were Gertrude and Otto Natzler. Check out their work. Beautiful crystals.
Marcia

I googled them but didn't see any crystalline glazes like ones in their book.

Bookseller Image

View Larger Image

Form and Fire: Natzler Ceramics, 1939-1972

Natzler, Otto; Joshua C. Taylor (Foreword); Lloyd E. Herman (Introduction); Daniel Rhodes (essay)


Description:
120 pages; an exhibition at the Renwick Gallery of 175 pieces described, about half are illustrated, most in full-page color. Many pieces include in their desciptions annotations by Otto Natzler who comments on Gertrud's throwing and on his glaze. Gertrud died in 1971 but left many bisque-fired pots to be glazed. Includes list of lenders, biographical notes, bibliography, two photos of the Natzlers, including frontispiece. Previous owner's name, otherwise clean throughout, pages crisp; covers only lightly shelf-rubbed, two light creases at the bottom corners. See image. Bookseller Inventory # 003644

Description from Abe's Books.com

I saw their curly cue crystalline work in person. In the book p. 54, 65, 80 the crystals are star shaped.
Marcia