Amaco High Fire Glazes

[Marla Stroup]

I am experimenting with some interesting construction techniques and have been using Amaco high fire white because it can be used on greenware and also bisque fired pieces.

The colors are not very appealing though and I will have to run test tiles of course but was just wondering if anyone has had any luck in layering or otherwise mixing any of these glazes from the High fire group?

Some are in a collection called Sabara Liquid Glazes and another HF Series is called Celebration Liquid Glazes. I just knew them as "High Fire" since their numbers were HF 11, HF 17,  etc.

[George Lewter]

No personal experience here, but on the AMACO website, they say,

"Layering two or more Sahara glazes on top of each other can create infinite effects depending on the different glazes you are using. The Sahara HF glazes are numerous: you can increase their number many times and their surface effects by overlapping them. Always test fire any combination that you are using before applying it on a good piece."

http://www.amaco.com/amaco-glazes-information/sahara-vases-2/

The Sahara line has been around for years. They are promoting the newer Potters Choice and especially layering those glazes.

[Marti Howell]

I have used quite a few of the Amaco PC glazes, but not many Sahara. The ones I would recommend are: Blue Rutile, Ancient Jasper, indigo Float, Iron Lustre,& Art Deco Green (over 1 coat of Albany Slip Brown), & True Celadon. They all need 4 coats. To get more red pizzazz out of Ancient Jasper I put Minnesota Clay's Iron Red on select areas (this is a wonderful glaze). The Amaco glazes that have been a disappointment are: Chun Plum, Deep Olive Speckle, Vert Lustre, & Seaweed, Textured Turquoise, Textured Tan. But, when i put Mayco's white Opal over Seaweed I loved it. The Yellow Oatmeal is a nice glaze over dark clay or previous glaze, but it is very light. You might want to try a few of the Mayco glazes. Blue Frost over Albany Slip Brown (Amaco 1 coat) or Speckled Plum is very striking. I can give you more info on these if you're interested. I haven't gotten satisfactory results with layering PC glazes. These are my opinions only from the results I have gotten.

[Norm Stuart]

I've found that the New Amaco Firebrick Red makes a great base glaze to layer other glazes on top of.

Firebrick Red is a non-fluid glaze base seemingly colored with a stain like Mason Stain Red 6088 (Cadmium Selenium) with red iron oxide.  It doesn't interact poorly like a Chrome-Tin red would.

Amaco provides examples of a number two glaze layering.

http://www.amaco.com/amaco-glazes-information/layering-potters-choi...

My husband made the curious figure below, covered entirely with PC-59 Deep Firebrick Red:

1.)  with  Amaco PC-49 Frosted Melon over the skin;

2.)  a rutile glaze over the Deep Firebrick Red on the hat and vest.  The rutile glaze is similar to an Amaco PC-20 Blue Rutile or a PC-23 Indigo Float. 

PC-28 Frosted Turquoise looks even better over PC-59 Deep Firebrick Red, likely a blue glaze muted with titanium dioxide.  My best guess is Amaco PC-49 Frosted Melon appears to be a green mason stain muted with titanium dioxide.

http://cone6pots.ning.com/photo/man-01?context=user

Amaco  Deep Firebrick Red   PC-59

Forsted Melon  PC-49

[Marla Stroup]

thanks for all the information. I am stuck at this point with only using the glazes that can be applied to greenware. The PC glazes need to be applied to bisque ware only? Or do you use it on greenware too?

I am just going to have to do some test tiles, no getting around it! I'll try to get photos of different combinations and share them with you.

thanks again

[Marti Howell]

I don't fire on greenware, but their are pics on the Amaco website that say "once fired". They are PC glazes. I think the potter is named Josh. They have a lot of info on there, but I've never seen where it said to use any of their glazes on greenware. Does it say that on the jar?

[Marti Howell]

Sorry, Norm, I just saw your reply. I tried Chun Plum over Firebrick & didn't like it. I will definitely try the Frosted Turq with it since I haven't found any combo that I like. Do you use only 1 coat of Firebrick? I really like what Albany Slip does under glazes, but found I could only use 1 coat of it. Very powerful. Did you mix the rutile glaze? Mayco has a rutile wash.

[Norm Stuart]

Most Amaco glazes are pudding thick to keep the ingredients fully suspended, so they likely contain added bentonite.  As a result one layer of glaze can look pretty thick, yet virtually all Amaco glazes turn out best with three layers.  It helps to thin the first coat to assure full application, or smooth the pudding thick glaze over the bisque with your finger.

Very few have a tendency to run, other than the fickle PC-4 Palladium, and to a lesser extent PC-2 Saturation Gold which seems to have been reformulated to flow less than it did four years ago  So three coats doesn't relate to glazes running in the kiln, unless you fire to Cone 7 and hotter where most of the Cone 5/6 glazes become very fluid.

Tin Oxide really adds a lot of shine and appeal to any glaze, creating variegation when used with iron oxide and color changes in other oxides, even when it is applied under another glaze. 

Why mention tin?  PC-32 Albany Slip is most similar to tin, iron, strontium glazes like Cream Breaking Rust with 13% tin oxide, which we make for an ingredient cost of $1.83 per dry pound. I'd guess a pint of Amaco contains one pound of dry glaze - so our pint costs about 90% less than what Amaco charges.  So there's a big incentive to make glazes.

Others iron-tin glazes are Creamy Rust, or the orange Bailey Shino, both with less tin oxide. I think all of these glazes are far more attractive than the original Albany Slip with lithium carbonate and tin oxide, which produces a plain-jane brown without much variation.

Rather than order a Rutile Wash, I'd just purchase rutile.  I'll know tomorrow how the Dark Rutile from US Pigment looks in "Honey ^6" and post a photo.  For us Light Ceramic Rutile from Laguna Clay is a dud, like adding ordinary titanium dioxide, creating a whitened matte glaze without the rutile streamers.

Mayco has an interesting selection of Cone 06 glazes which contain Rabco Specs.  http://www.rabcospecks.com/

For us, an all-in-one Medium-Slow firing of greenware to Cone 6 is more costly than firing Medium-Slow to bisque, applying the glaze and firing again to Cone 6 at Medium-Fast.

We do often fire Cone 06 glazes along with Cone 04 bisque to a compromise Cone 05, but this the carbon burning-off poisons Cadmium-Selenium red glazes - and those with glazed pieces in the bisque firing are not happy if any of the greenware pops-off some clay bits.

Marti Howell said:

Sorry, Norm, I just saw your reply. I tried Chun Plum over Firebrick & didn't like it. I will definitely try the Frosted Turq with it since I haven't found any combo that I like. Do you use only 1 coat of Firebrick? I really like what Albany Slip does under glazes, but found I could only use 1 coat of it. Very powerful. Did you mix the rutile glaze? Mayco has a rutile wash.

[Marla Stroup]

Yes, it is on the jar of both the Celebration Liquid Glazes and the Sahara Liquid Glazes: Apply 3 brush coats on green-ware or bisque. Fire to witness cone 5. I fire to cone 6 and don't have any problems. The kiln shuts off at 2236.

Marti Howell said:

I don't fire on greenware, but their are pics on the Amaco website that say "once fired". They are PC glazes. I think the potter is named Josh. They have a lot of info on there, but I've never seen where it said to use any of their glazes on greenware. Does it say that on the jar?

[Marti Howell]

Well, that's new to me that some of the Amaco glazes can be used on greenware. Still,I agree that you probably don't save much by applying to greenware & I would REALLY need to know my glaze to take the risk.

[Marla Stroup]

I agree with being hesitant to use on greenware. It just seemed weird for sure. I am experimenting with a construction method that uses slip and gauze. Being able to skip the bisque firing lets me avoid the very fragile stage between the bisque and glaze firing so for me it is very useful. My last piece consisted of bisque fired clay AND greenware and it even worked on that. It is pretty much experimental construction.

Marti Howell said:

Well, that's new to me that some of the Amaco glazes can be used on greenware. Still,I agree that you probably don't save much by applying to greenware & I would REALLY need to know my glaze to take the risk.

[Marti Howell]

Sounds very interesting! When you get something you like you should post a pic. (I need to learn how to do that myself). I like the Sahara yellow oatmeal even though I would call it a cream. Maybe you can add some stains to the glazes to brighten them up. Good luck!

[Marla Stroup]

Just to clarify, please read the fine print on each bottle of glaze to see if it is recommended for greenware or not. I'm not sure that every glaze in a certain line could be applied to greenware.

I have three recent photos posted, all of which incorporate the experimental gauze/slip method I've been fooling around with. The one called icicles is completely gauze/slip construction, meaning there is no clay body at all. The other two start with a clay body and have the g/s added to them.

I have three new pieces that should be finished in the next few days. I will post photos!

I haven't tried the Sahara yellow oatmeal.

Marti Howell said:

Sounds very interesting! When you get something you like you should post a pic. (I need to learn how to do that myself). I like the Sahara yellow oatmeal even though I would call it a cream. Maybe you can add some stains to the glazes to brighten them up. Good luck!