From a recent Clayart post by Alisa Clausen.  I rounded her recipe a bit, see below.  I guess a glaze guru with a fancy-schmancy glaze calculator could fix this so it added up to 100 nicely . . . A beautiful pink/purple/red.  Lots of character.

Note:  I have not tested this at all for food safety.

CT Red recipe

EPK	8.1
Silica	32.3
Gerstley Borate	21.2
Nepheline Syenite	17.2
Talc	1.0
Whiting	20.0
	-----
	99.8

Add:

Chrome	0.15
Tin Oxide	5.05

 

Glaze notes, Raspberry as Blue

Also from Alisa.  I'm not much into this screaming-blue-meanies color, so I'm currently testing it out as purple.  Check back for that image (it's in the kiln cooling as I type).

Raspberry as Blue Recipe

See "Mastering Cone 6 Glazes" by John Hesselberth and Ron Roy.

Add:

Chrome	0.15
Tin Oxide	5.05

Glaze notes, Oilspot

A recent discussion on Clayart had me searching for this recipe.  I'm not sure now where I found it, but it was somewhere on the archives.  I hope it's okay to post here.  Many versions of this running around.  I just found one on the frogpondpottery.com site I will probably try next.

I didn't get any "oil spots" on my test tube at all.  I'm not sure if my results are typical or not.  Very glossy, very dark blue that breaks to green.  Pretty, but very similar to the results I have 50% of the time with Ron Roy and John Hesselberth's "Variegated Slate Blue." 

Note:  I have not tested this at all for food safety.

Oil Spot recipe

Nepheline Syenite	35.0
Silica	30.0
Whiting	18.0
Ferro Frit 3134	12.0
OM-4 Ball Clay	5.0
	-----
	100.0

Add:

Tin Oxide	8.0
Copper Carbonate	4.0

My general firing schedule

• 80° C / hour from start to ^5
• "Kristin hold" for around 15-20 minutes = when 6 cone starts to bend, I turn down dials a bit until freestanding cone 6 tip is level with top of base.
• Shut off kiln
• At 1065° C I begin a slow cool
• Cool at rate of 40 - 80° / hour to 800° C
• Shut off kiln (go to bed!)
• Open a crack in the morning, generally around 300° C
• Unload at about 200° C