[A very simple cone 6 glossy base]

This is a clear glaze that I use, fairly simple and if you add 8% rutile it becomes a beautiful white gloss.

Oyster Gloss

EPK –--------------------- 6

Dolomite –------------- 12

Gerstley Borate ----- 23

Flint –-------------------- 27

Nephelene Syenite - 32

And another clear using less Gerstley Borate.

Gloss

EPK –----------------------- 6

Dolomite –-------------- 12

Gerstley Borate –----- 12

Flint –--------------------- 30

Nephelene Syenite -- 40

[A very simple cone 6 glossy base]

I used to use Frit 3134 as a substitute for Gerstley Borate back in the 80's when there was a Gerstley Borate shortage. I found it flocked my glazes the same way Gerstley Borate did. I concluded that there must be enough free Boron because of the low Silica and Alumina content in the formula that it remained soluble. Boron is a glass former. Anyone who has thrown Borax on a raku pot and found it created a beautiful glassy glaze has seen it in action. Overtime the glaze will desolve in water alone. I have a potter friend who used a beautiful clear glaze she was given by a well known ceramist that had way to much boron in it and overtime her glazes deteriorated.

To answer your question Frit 3134 is not a complete glaze. It is used as a flux and needs more silica otherwise the free Boron will soften the glaze. There are a lot of  great cone 6 clear glazes out there and davidh4976 glaze is probably a good one. Frit 3195 is much closer to a complete glaze.

[Tweeking Laguna Dynasty Tangerine Ice, Ruby Dust, etc...what is an ingredient?]

I think Min is correct that this is a microcrystalline  glaze and that's what is causing the dappled effect and the satin finish. I find it very useful to use a strong magnifying glass to see into the glazes and actually see the microcrystals. Often decreasing the microcrystals in the glaze will strengthen the color. That can sometimes be accomplished by firing higher or by adding more flux to the glaze.  Sometimes microcrystals can have a color of their own. The presence of titanium will often give a silvery look to microcrystals but the presence of iron will make them copper or golden. These are good things to understand and maybe guide you in your experiments even though you are mixing commercial glazes which are hard to know what ingredients they may contain.

[Tweeking Laguna Dynasty Tangerine Ice, Ruby Dust, etc...what is an ingredient?]

I find that Wolastonite as a raw ingredient for adding calcium and silica will promote micro-crystals better than using Whiting and Flint.

[Deformed walls when pouring out slip of molds]

I have found that water chemistry can much affect clay slips jelling and thinning. Best not to increase your deflocculant. I have found that just a teaspoon or two of common household lye in five gallons of slip will thin out your slip and much alleviate jelling.

[Strange blow outs during bisque fire]

Just saw this post and I would add that excess water could well be the problem. I glaze all but my very large pots green, that means I don't bisque them. I use a clay body that has no grog in it and no fireclay. Porcelains and slipcast pots work well in once fired pottery because the are very tight and don't absorb water quickly. I have to be very careful when I apply my glazes because I can get the blow outs you describe.

[Cone 6 slip casting recipe]

Hi Betty,

After looking at my most recent notes I realize I use Pioneer Kaolin instead of EPK. For many years I used EPK and the reason to use Pioneer was to get a whiter fired look.

Another trick I use if the water is hard is to add a teaspoon of household lye. It will make the slip much more fluid. Also you can use up to 20 lbs of water.

16 lbs equals 2 gallons if you prefer to measure it that way and just add no more than 4 more pints.

[Cone 6 slip casting recipe]

Hi Betty,

For a couple of decades I have used a cone 6 white firing slip that I have never had trouble with. No cracking or warping or glaze fit problems.

I always made 80 lbs in two 5 gal. buckets so this is the recipe,

Water ............... 16 to 18 lbs with 5 Tbs Davan #7

Ball clay .............3 lbs

EPK ..................15 lbs

Flint 325 ........10 lbs

Neph Sy ......... 12 lbs

[How to add speckles to a claybody?]

I am firing at cone 6 in an electric kiln. I make my own clay for many reasons. Most of the clay bodies available have way to much manganese and therefore very dark. Manganese makes a very cold dark brown and is poisonous. I was looking for a warm rich orange brown look. For that I chose iron magnetite. Also I found that the commercial blends do not have good glaze fit for my glazes. I also raw glaze (no bisque) and need a very tight body without any coarse materials in it like grog or fireclay that would absorb excess water to rapidly. I say this to warn you about why my claybody is formulated the way it is but it is a good starting point and one can add grog or substitute fireclay for the #6 tile.

Cone 6 stoneware

#6 Tile ..................24 lbs

Ball clay .............. 24 lbs

Goldart clay ..... 20 lbs

Redart clay ,,,,,,,,, 8 lbs

Flint ,,,,,,,,,,,,,,,,,,,, 12 lbs

Feldspar ............ 12 lbs

Iron magnetite ...120 grams

[How to add speckles to a claybody?]

Jumping back a bit to glazenerd's suggestion, granular magnetite, since it is a form of iron does it's color reflect a warmer iron color than granular manganese which is a blackened brown. I have used granular Illmenite but it produces very fine but very warm iron specks.