Raku Pottery Glaze: Forbes Cobalt Crust #2

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Gerstley Borate                  57%
Synthetic Bone Ash            19
Nepheline Syenite               10
EPK                                    9
Silica                                   5

Add:
Copper Carbonate                 8
Cobalt Carbonate                  2

Fired to 1900 F with heavy post firing reduction using newspaper.  No burping.

Raku Pottery Glaze: Forbes Copper Satin Matte, Variation 2

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50 Gerstley Borate
20 Frit 3269
15  Nepheline Syenite
15  Lithium Carbonate

Add:
17 Synthetic Bone Ash
6  Tin Oxide
5  Copper Carbonate
1  Cobalt Carbonate

Photo is of two test tiles both fired in the same kiln to 1875 degrees F and reduced in the same 10 gallon can with 6 sheets of newspaper (3
torn into strips).  Lid was placed on the can immediately which produced a medium reduction.  Can was not burped and tiles were left
to cool.

Raku Pottery Glaze: Shiny Copper Flash

The flashing will vary with each firing. This was fired to 1875F and given medium post-firing reduction using newspaper after pulling from the kiln.

Shiny Copper Flash

%75 Gerstley Borate
      %12.5  Nepheline Syenite
      %12.5  EPK

    Add:
       %8 Copper Carbonate
       %2 Cobalt Carbonate
     

Raku Pottery Glaze: Copper Matt

The flashing will vary with each firing.  Both of these were fired to 1875F and given medium post-firing reduction using newspaper after pulling from the kiln.

Copper Matt

Add

%75 Gerstley Borate
      %12.5  Nepheline Syenite
      %12.5  EPK

    Add:
       %8 Copper Carbonate
       %2 Cobalt Carbonate

  Add:
       %16 Synthetic Bone Ash

     

Raku Pottery Glaze: Emerald Green Copper Flash

The raku glaze of the month is a greenish blue with copper flashes that will vary from firing to firing.

Emerald Green Copper Flash Glaze

Frit 3110:                                  30%
Frit 3124:                                  20%
Gerstley Borate:                       30%
Nepheline Syenite:                   20%
Copper Carbonate:                   5%

April Glaze : Lime Green Crackle

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Lime Green Crackle glaze is fired to 1900 degrees F, pulled from the kiln and reduced in a small can with newspaper.

RAKU POTTERY GLAZE RECIPE

Frit 3110                  58%
Frit 3269                  10
Nepheline Syenite:   22
EPK (Kaolin)             5
Silica                        5
Add:
Chrome Oxide          .4 (point 4)
Tin Oxide                  3
Hectorite                   2  or Bentonite  1%

This month's glaze is a revision of my March Glaze called Lime Green Crackle. Stay tuned for a silver glaze recipe next month!

This glaze is fired to 1900 degrees F, pulled from the kiln and reduced in a small can with newspaper.  Lid is put on immediately. Wait about 2 1/2 minutes and remove the lid.  Rub the top of pot with torn newspaper using gloves.  Once paper ignites cover can again immediately and let cool (you may have to use a torch to reignite the paper).