Raku Glaze

Raku Glaze

January Raku Pottery Glaze: Forbes Cobalt Crust #2

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

Copper Carbonate                 8
Cobalt Carbonate                  2
Silica                                   5

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

Raku Glaze

December Raku Pottery Glaze: Forbes Copper Satin Matte, Variation 2

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

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 Glaze

October 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.

Oct Glaze of the Month

Shiny Copper Flash

%75 Gerstley Borate
      %12.5  Nepheline Syenite
      %12.5  EPK

       %8 Copper Carbonate
       %2 Cobalt Carbonate

Raku Glaze

September 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


%75 Gerstley Borate
      %12.5  Nepheline Syenite
      %12.5  EPK

       %8 Copper Carbonate
       %2 Cobalt Carbonate

       %16 Synthetic Bone Ash


Raku Glaze

August 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.

Raku Pottery Glaze of the Month | August

Emerald Green Copper Flash Glaze

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

Raku Glaze

June Glaze: Forbes Midnight Blue

Midnight Blue is a rich cobalt blue with red streaks in post firing reduction.  Stay tuned for this month's pot which features previous glazes of the month:  Blue Moon, Lime Green and Sassy Fat White/Silver Slither, in addition to this month's Midnight Blue.  

Forbes Midnight Blue Glaze

Frit 3110                          68%
Custer Feldspar                18%
EPK (Kaolin)                      9%
Lithium Carbonate               5%
Copper Carbonate               4%
Cobalt Carbonate                2%
Hectorite                            2% (or Bentonite 1%)

Raku Glaze, Press & News

May Glaze : Forbes Sassy Fat White

With Silver Nitrate added I call this glaze Silver Slither, which is pictured.  This glaze has to be fired hot to about 1950F for the platelets to form beads.  it looks different on top of a variety of base glazes as you can see from the photos.  Works best on shoulder of pieces or on a more horizontal surface.  Mix on the thick side.  I usually apply a very small amount at a time by either pouring or brushing.  When I pour it, I often will blow on it to move it around.

Raku Pottery Glaze Recipe

Frit 3110                        85%
Nepheline Syenite            5
EPK                              10
Tin Oxide                        7
Magnesium Carbonate    34
Hectorite                         2  or Bentonite    1
Optional:  Silver Nitrate    2

Raku Glaze, Press & News

March Glaze: Forbes Lime Green

As shown fired to 2000F with pyrometer so the silver glaze will melt.


Frit 3110                     54%
Nepheline Syenite    21%
EPK (Kaolin)               10%
Silica                           10%
Lithium Carbonate     5%
Chrome                       .4% (that's point 4)
Tin                               3%
Hectorite                     2%  (or 1 Bentonite dry mixed)

A note about Hectorite:  It's a suspender in powder form similar to Bentonite except it doesn't have to be dry mixed with the other chemicals.  It's not a common raku pottery glaze chemical and you may have to search for it on the web. I purchased mine at Highwater Clays, but they don't carry it anymore due to lack of demand (nobody knew what it was used for).

Raku Glaze

February Glaze: Blue Moon

Glaze fired to 1900F.


Silica                             30%
Frit 3134                        20%
Nepheline Syenite        15%     
Lithium Carbonate.       15%
EPK Kaolin                     10%
Strontium Carbonate    10%
Tin Oxide                        7%
Copper Carbonate         4%
Bentonite                         1%




This is a stable blue and red glaze.  1/2% Epsom Salts can be substituted for Bentonite.  This glaze produces some incredible raku pottery and is one that I developed several years ago.  This picture is the results of the raku glaze fired to 1900F. It remains a staple in my studio.  See more of my work by visiting my raku pottery store.  To learn more about my process, visit my raku firing page.