oldlady Posted August 1, 2016 Report Share Posted August 1, 2016 this glaze came from my friend Robin Teas while she worked at Lord Fairfax comm. college in va. it was her recipe and fired in a gas kiln. i know the pinkish effect is from reduction firing but i wonder if anyone has a glaze recipe for something matte, green and able to show fine texture without flattening it out. Robin has given me several recipes to try but it does not hurt to ask the whole community the question. Link to comment Share on other sites More sharing options...
Pres Posted August 1, 2016 Report Share Posted August 1, 2016 This glaze may be better at cone 6 as a combination of two glazes, a cone 6 raspberry with a copper green. I have no idea how you could do it without two glazes of this sort. I think I would start with something like Van Gilder's raspberry, and some green that is semi transparent. best, Pres Link to comment Share on other sites More sharing options...
LinR Posted August 1, 2016 Report Share Posted August 1, 2016 Wow, if you find a recipe would you post it? Nice glaze! Lin Link to comment Share on other sites More sharing options...
Joseph Fireborn Posted August 1, 2016 Report Share Posted August 1, 2016 Pinnell Strontium Green is pretty similar, although a bit darker, but you could modify the copper amounts and probably get a closer version. However you wouldn't get pink out of it though would need another glaze for that. I can't tell if it is matte though or satin. Link to comment Share on other sites More sharing options...
Magnolia Mud Research Posted August 1, 2016 Report Share Posted August 1, 2016 I would start with my favorite clear cone 6 glaze and do a line blend with copper carbonate. LT Link to comment Share on other sites More sharing options...
Marcia Selsor Posted August 1, 2016 Report Share Posted August 1, 2016 My favorite clear glaze with copper carb. goes red in reduction. Marcia. Link to comment Share on other sites More sharing options...
oldlady Posted August 1, 2016 Author Report Share Posted August 1, 2016 i am not trying to get the pink, i am looking for a matte green able to show fine texture without flattening it out. at cone 6 . in oxidation. Spearmint does not work. i have strontium green. i have oribe green, too glossy. i will try Wettlaufer's 18 which is a really nice matte glaze. i have tried it with 4% copper, which is very dark. will try 3%. any other suggestions? Link to comment Share on other sites More sharing options...
Magnolia Mud Research Posted August 1, 2016 Report Share Posted August 1, 2016 Take your glossy green and add Zircopax in a line blend. LT Link to comment Share on other sites More sharing options...
glazenerd Posted August 2, 2016 Report Share Posted August 2, 2016 Lady Can you get me a close up of the 3rd picture (inverted bowl) from the foot to where it breaks red please? Nerd Link to comment Share on other sites More sharing options...
dee3 Posted August 2, 2016 Report Share Posted August 2, 2016 Hi, there's Helens Olive Matt/Soft RedCone 6-9Reduction or Oxidation Nephelene Syenite 75Whiting 10Dolomite 10Bentonite 4Silica 5Copper Oxide 2 Comments: Cone 5-6 (electric kiln, oxidation) gives Olive Matt; Cone 9 (electric kiln, oxidation) gives Green/Orange Gloss; Cone 9 (gas kiln reduction) gives Soft Red Gloss. You could try lowering the copper as it might be a bit dark. Dee . Link to comment Share on other sites More sharing options...
oldlady Posted August 2, 2016 Author Report Share Posted August 2, 2016 nerd, sent you a pm. dee, do not think i have copper OXIDE, i always use the carbonates because the oxides are so strong. even as a carbonate, copper is strong. will try this recipe, today is another glazing day. Link to comment Share on other sites More sharing options...
WildRumpus Posted August 2, 2016 Report Share Posted August 2, 2016 We use a very pretty satin turquoise that doesn't get the pinks as much but on brown clay changes from orange to turquoise very subtly. It pairs well with other glazes as well. I use it as a staple because it looks very different (but still very good) on my 2 different clay bodies. Link to comment Share on other sites More sharing options...
glazenerd Posted August 3, 2016 Report Share Posted August 3, 2016 Lady: Posted a picture in the gallery of the most recent (red in oxidation) test. It is just now starting to break red, with deeper green. So where it goes from here. Nerd ^6 by the way. Link to comment Share on other sites More sharing options...
Rex Johnson Posted August 3, 2016 Report Share Posted August 3, 2016 Coyote has quite a few satin glazes that look similar. You could use the white satin and add the colorant of choice. Both electric and gas fired cone 6 are very stable and predictable. Link to comment Share on other sites More sharing options...
glazenerd Posted August 3, 2016 Report Share Posted August 3, 2016 Lady: My first attempt at red in ^6 oxidation: Red/ deep green just barely coming through. Second attempt at red in ^6 oxidation 2 hour soak involved. Forgot to titrate PH downward- crawling -opps!! Should have something for you shortly. Nerd Link to comment Share on other sites More sharing options...
oldlady Posted August 4, 2016 Author Report Share Posted August 4, 2016 thank you, rex. i mix my own glazes and this will be a color i will use on a hundred pieces so buying it would be prohibitive. nerd, thank you, hope it works. again, i am not interested in the pink, just a nice matte green that allows texture to show through. so many matte glazes flatten the surface totally so nothing shows from all the work i do to put the texture on. leaves do not make deeeeeep impressions. Link to comment Share on other sites More sharing options...
oldlady Posted August 27, 2016 Author Report Share Posted August 27, 2016 as of august 26, 2016 dee3 and anyone else who might try Helen's olive matte glaze shown above. thank you, dee3, it turns out that the recipe is in my glaze book but it is one i had never tried. added the attribution to Helen though i do not know who she is. it is a beautiful color, the glaze is easy to make but it does powder off when handled to place in the kiln. i tried it on 2 different shapes both inside and out. sadly, all of the tests have crazing way down inside the glaze. i can't see the crazing on the surface, but it is there. the color is not so olive as the name suggests but i like the color. it does seem to cover texture but i am not sure if it would be too much. the pattern i drew into the test bowl disappeared. am out of room for photos right now, i thought they added more capacity during the last website revision but i am wrong. can anyone suggest a modification to prevent the crazing? Link to comment Share on other sites More sharing options...
glazenerd Posted August 27, 2016 Report Share Posted August 27, 2016 Hi, there's Helens Olive Matt/Soft Red Cone 6-9 Reduction or Oxidation Nephelene Syenite 75Whiting 10 Dolomite 10 Bentonite 4 Silica 5 Copper Oxide 2 Not surprised at all to see clay/glaze interface checking Nep SY has one of the highest COE values among fluxes. The above recipe has an estimated COE value of 9.25 ( some programs post it as 92.50) Well above any porcelain or stoneware COE values. In addition, the NaK20 are way over formula limits set by Hesselbeth and Roy. It is an extremely fluid glaze: which in your case is desirable so that it flattens out uniformly over the detailing work. By reducing the Nep Sy, you likewise lower the COE: which brings it in line with most clay values. By replacing it with silica: you still have a fluid glaze that should flatten out equally as well. The above recipe falls seriously short in regards to silica formula limits: so silica additions are required to conform to minimum formula limits. That said: Nep Sy 50.0 Dolomite 15.0 Whiting 11.0 Bentonite 4.0 Silica 24.0 Est COE 8.09 (a full point under the original recipe: which should cure the grazing issue.) Did not mess with copper carb, it is a colorant that you will need to adjust to reach your desired hue. Try mixing equal parts of EPK and Bentonite: and use that mix to replace the 4.0% in the recipe. EPK makes a good glaze hardener as well: might help with the powdering/flaking issue. The additional magnesium in the dolomite will deepen the green a bit: might hit your olive hue better. Nerd Link to comment Share on other sites More sharing options...
oldlady Posted August 27, 2016 Author Report Share Posted August 27, 2016 thank you, nerd. i will try your suggestions. it is great that you are willing to share knowledge in simple terms so even i can sort of understand. will try that revised recipe. if i got it right, eliminate bentonite 4 and use bentonite 2 plus EPK 2. i did use copper oxide. will try to adjust pics so i can send what happened but the guild picnic is here tomorrow and there is a LOT to do. Link to comment Share on other sites More sharing options...
glazenerd Posted August 27, 2016 Report Share Posted August 27, 2016 if i got it right, eliminate bentonite 4 and use bentonite 2 plus EPK 2. Yes maam- but that revision is an attempt to help resolve the glaze dusting issue. If you see no benefit- go back to the straight 4% bentonite. Here is the analysis of the glaze before, and after revision: Original Recipe Hesselberth & Roy ^6 Limits Revised recipe 0.437 Kna(o) 0.10-0.30 0.259 0.146 MGO 0.00-0.30 0.209 0.416 CaO 0.20-0.60 0.502 0.476 Al2O3 0.25-0.50 0.320 2.28 SiO2 2.50-4.00 2.43 Si/Al 4.80 Si/Al 7.53 COE 9.25 COE 8.09 Normally clay additions are often used to increase silica and alumina ratios. However, in this case I wanted the alumina lowered and the silica raised to increase the fluidity of the glaze so it will flatten out against the detailing. The silica remains under limits in the revision: which is easily addressed later. See how it works first before making any additional adjustments. >>> I would recommend close attention be paid to application rate of the glaze: it will be fluid. The increase in magnesium (MGO) should help with the "olive" hue you are looking for. Nerd Please recheck the revised recipe: I noticed a typo on the silica amounts. Link to comment Share on other sites More sharing options...
bciskepottery Posted August 27, 2016 Report Share Posted August 27, 2016 Nerd, Would the increase in Si:Al ratio shift the glaze from matte/satin to more glossy? Link to comment Share on other sites More sharing options...
glazenerd Posted August 27, 2016 Report Share Posted August 27, 2016 Bruce: Yes it will. Playing a bit of a shell game here. Lady needs a glaze that will lay down, and not cover up her detailing work. So I kicked the legs out from under it by lowering the alumina, to offset the fluidity lost with removing the Nep Sy. I increased calcium and magnesium (low flow alkali) to replace the strength lost in the alumina. In addition, dolomite is used in glazes in higher percentages to help create the matte.(magnesium). Hopefully the trade off works: might have to increase dolomite further. There are other matting agents that could be added as well. I work glaze a bit different than most: I aim for the function first: then add the aesthetics. The additional magnesium should also help her hit the olive mark. Again, glaze application/thickness will be a crucial point. Oxide colorants like to pool in fluid glazes- trying to avoid that as well. Nerd Link to comment Share on other sites More sharing options...
oldlady Posted August 29, 2016 Author Report Share Posted August 29, 2016 OK, nerd, if i understand it, my recipe now reads neph sy 50 silica 24 dolomite 15 whiting 11 total 100 bentonite 2 EPK 2 copper oxide 2 if that is correct, i will make it. there is little time between now and sept 10 for testing tiny tweaks so i hope this is the solution, thank you. will make it up tomorrow another note, the matte is nice but the color and the transparency is critical. the test showed a nice matte going shiny. will add photo! Link to comment Share on other sites More sharing options...
glazenerd Posted August 29, 2016 Report Share Posted August 29, 2016 Lady: you have it. It will go a bit more glossy, but hopefully the additional mag will offset some of that. Get a reg and close up pic if you can. The big adjustment will be the amount of oxide: that is solely a judgment call on your part. I expect it to be rather clear given the silica content. High levels of flux can cloud as well: that has been resolved as well. Nerd Link to comment Share on other sites More sharing options...
glazenerd Posted August 30, 2016 Report Share Posted August 30, 2016 Lady: Still studying the pictures you posted. You noted on the cup that a piece on the rim fell off (shivering.)? The first picture is what has my attention: it is a bit blurry, but I can see the COE issue you were speaking to: crackle/glaze. Am I seeing a color shift up on the rim to a tan color? If so, then you have a higher iron content clay- stoneware perhaps. What kind of silica are you using? Nerd You might want to do a test with 1.50 and 1.75% copper carb.: green strikes me as being a tad strong. Link to comment Share on other sites More sharing options...
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