Glaze Color Q? On Sapphire Blue

[Wyndham]

I've got a request for a blue/blue green glaze for a cone 6 cassarole. I'm thinking of using Frogpond's sapphire blie but changing the colorants to about 3/4%cobalt carb and about 1 or 2 % copper carb instead of the 1.5% cobalt carb and the 4% rutile.

The glaze I'm trying to match is a clear dark bluebreaking to green blue.

I'm hoping someone her has testes different colorants in this base.

Please let me know some thoughts on this, if you can.

Thanks Wyndham

[Wyndham]

replying to my own thread.

I just peeked in the kiln, still a tad hot, 500 deg! But an interesting gloss blue

I used frogpond's Sapphire blue base

frit 3134             37%

G200                 16%

Strontium carb     4%

EPK                    26% I changed this to 13% epk & 13% calcined epk 13%

silica                   17%

 

I changed the colorants to 1% cobalt carb & 1.5 % copper carb

 

At cone 6 this gave a very pleasing blue teal but I'm looking for a darker color so my next teast will be adding some iron ox, maybe 3-4 %

I don't want the rutile that's in the original recipe because it will cloud up the transparancy of the glaze.

 If anyone has any experience with a darker teal blue, please chime in.

 

I'll try to post photos later

Wyndham

[Pres]

I use a teal blue from the Van Gilder glazes. It may help you out, or at least give you a start point. This is often used as a base for under some other glazes dipped/sprayed over top.

 

Teal Blue     Compound Empirical ...........50 75

Custer Spar.................................... 20 1000 1500

Frit 3124 .........................................20 1000 1500

Wallostonite ....................................20 1000 1500

EPK-Kaolin ......................................20 1000 1500

Silica ................................................20 1000 1500                

Total in grams ................................100 5000 7500        

 

Cobalt carb......................................... 1     50  75

chorme oxide.................................... 0.5    25  37.5

 

Whoops the way it put it in is confusing, but first number is empirical, second makes 5000g third makes 7500g batch. This is how I have my Word Spreadsheet set up.

[Wyndham]

Thanks, that's the way my recipe book is set up %, then 1000,5000,10,000 grm

That bit of chrome might just do the trick, copper & Iron shift green too quick.

Anyway what i posted came out a nice lite cobalt blue that shows up texture well

I'll test it oin the next firing. Looks like a variation on Hanson's 5 20"s which has always been a good base.

Thanks

Wyndham

[oldlady]

pres,  i found that the software takes out as many spaces as it can so if you want to separate figures you could use periods.  

 

Rio...............4

cobalt...........2  like this.

 

don't know how wyndham got his spacing to stay put.

[Wyndham]

I don't know, I just put it in

Wyndham

[Pres]

Wyndam, I edited it to match up. Thanks for the help Old Lady!