Orange Red Iron Glaze

[Dick White]

4 hours ago, GreyBird said:

What clay body is it on?

It is a proprietary blend I make that's so proprietary I don't know what's in it (studio reclaim of whatever the students dump in the bucket...)

[GreyBird]

On 8/28/2018 at 11:34 PM, Dick White said:

Everybody who said iron reds are tricky - is right. Everybody who is having trouble with iron reds coming out brown - join the crowd. I don't fully understand the exact chemical problems at the ionic valence level, but from an empirical standpoint, the troubles  in the US pottery world seem to have started when NYTAL talc when out of business and talc moved to Texas, and about same time, Mad Cows started mooing and real bone ash became scarce and replaced by synthetic TCalP.  Two suggestions which I have found successful -

1) refire your muddy brown iron glaze in your next bisque firing (following the usual glaze loading protocols, i.e., no touching). Iron reds need an extremely slow downfiring, to about 1700F to turn red. A slow upfiring back to bisque temperature is functionally about the same.

or,

2) change your glaze recipe one called Orange Street. Sample picture below.

EPK - 3.6

Gerstley - 14.9

Minspar soda spar - 39.5

Silica - 12.3

Texas Talc - 12.4

Dolomite - 7.1

Synth. Bone Ash - 10.2

RIO - 10

Crocus Martis - 5

Well, One theory down... I re-fired in my next bisque and it came out like mud (see pic). perhaps it needs to be thicker. or perhaps ill try the other recipe.

 

[GreyBird]

OK, so I mixed up Orange Street and tried it on two test tiles. One Porcelain and one Stoneware... It looks fantastic on Porcelain. For me it did anyway  On the stoneware it came out almost black with a hint of red on the backside near where it pooled a bit along the top lip of the tile. See Pics...

[glazenerd]

Mary:

as DW pointed out, there is chemistry involved. That said, how FeS2; the most common iron source in American reacts, and how FeO3 (hematite) reacts, and how FeO4 (magnetite reacts are all different. Before my fellow potters chime in and state the obvious: all iron reduces to FeO- that is not what I am referring to. My point Mary,  Hudson has magnetite; and the final colors will not result in the old Albany, or Red  Art, or Newman Red.

t

[GreyBird]

39 minutes ago, glazenerd said:

Mary:

as DW pointed out, there is chemistry involved. That said, how FeS2; the most common iron source in American reacts, and how FeO3 (hematite) reacts, and how FeO4 (magnetite reacts are all different. Before my fellow potters chime in and state the obvious: all iron reduces to FeO- that is not what I am referring to. My point Mary,  Hudson has magnetite; and the final colors will not result in the old Albany, or Red  Art, or Newman Red.

t

Yes, I understand and I'm not trying to change that. I liked the original color that came out when I used it in the Original Albany recipe but which like the original Albany recipe shivered, so I'm just looking for it to be itself but not shiver. OK but hold on... I thought you were responding to the Hudson Clay thread. This is a completely different thread and there is no "Hudson" clay used here

[Mark C.]

(It looks fantastic on Porcelain)       Thats why I use porcelain-the glazes POP-also its very hard and chip resistant.

[GreyBird]

12 hours ago, Mark C. said:

(It looks fantastic on Porcelain)       Thats why I use porcelain-the glazes POP-also its very hard and chip resistant.

I agree, though I also really like the look of the unglazed Stoneware that I use so I often leave a portion of some pieces, like my mugs, unglazed (see pic). For that reason I am always looking for glazes that look really good on stoneware. I am definitely going to make some porcelain stuff for the OrangeS Street glaze. I don't see anything in the recipe that would cause it to be non-food safe, I could be wrong. Does anyone else know if this recipe is food safe?