Cone 013 = 807 ℃
Glaze Fire Ceramic 800 degrees C – Lead Free (71/100)
Lumen Rubrum glazes:
Lumen Rubrum glazes are designed for the temperature span between 750-850 degrees Celsius, Cone 013 = 807 ℃
Lumen Rubrum, meaning “Red Light” in Latin, refers to the pot’s wonderful red glow in the kiln at this temperature.
Glazes from the Egg Kiln:
All glazes here are once-fired, Lumen Rubrum glazes, meaning pottery glazes for 750-850 ℃. Cone 013 = 807 ℃. And brushed or dipped onto dry clay, before being dried in the kiln with a small flame, so the water from the glaze vaporizes before it seeps in and moistens the clay.
Glaze receipts in general:
40-60% low fire flux (for melting).
10-20% high fire flux (stability, not volatile or evaporates).
10-40% Quarts (glass former).
10-30% clay (to shrink the glaze together with the pottery).
Once fire glazes need to contain more clay to be able to stick to the raw clay, and also to shrink together with the clay vessel.
These glaze receipts here are measured in volume! not in weight.
Here I both try to adapt my glazes to 750-850, and also get a grip on once-firing. It needs more experiments, so:
This page is a work in progress
(LR 001) (started to rain, did not reach max temperature)
White glaze – (reference Q04 hvit glassur)
Did not shrink with the clay and could be peeled off, would it still be white when melting?
NY
2 Gerstley borate
4 High alkali frit P2962.1
2 Magnesium Carbonate
1 Chalk
2 parts Kaolin
4 Quarts
(LR 002) (started to rain, did not reach max temperature)
Black thin wash
Need a higher temperature, looks interesting but more glossy than expected
1 Gerstley borate
1 Sodium bicarbonate (household product)
3 Quarts
1/4 Copper Carbonate
(LR 002b)
Black thin wash
Trying with a variation
1 Gerstley borate
1 Sodium bicarbonate (household product)
1 Light Rutile
3 Quarts
1 Tin Oxide
1/4 Red stain
(LR 003) (started to rain, did not reach max temperature)
The darkest hour
Not as interesting as thin, it needs a good thickness before it melts out as a beautiful glaze
2 Gerstley Borate
3 Sodium bicarbonate (household product)
3 Nepheline Syenite
1 kaolin
1 Quarts
2 Iron oxide black
(LR 004)
Crackled green
4 Borax Frit P2953.1
1 Ballclay
5 Quarts
1 Iron Oxide Green
(LR 005)
Wood ash glaze
4 Gerstley Borate
2 Feldspar Soda
3 Wood Ash
1 Kaolin
1 Iron Oxide Red
(LR 006)
White thin glaze
5 Borax E Frit P2953.1
5 Talc
(LR 007)
Best white cover glaze for terracotta?
6 Ferro Frit 3134
1 Chalk
1 Kaolin
3 Quarts
(LR 008)
Thin glossy wash
7 Borax E Frit P2953.1
3 Nepheline Syenite
3 Blue Stains
(LR 009) (started to rain, did not reach max temperature)
Chocolate black glaze
Oh, not much chocolate, strange glaze
2 part Sodium Bicarbonate (Soda Ash/Baking Soda)
2 part Borax
1 part Feldspar Soda
3 part Quarts
2 part Kaolin
1/2 part Bentonite
1/2 part Iron Oxide Yellow
(LR 010)
My best food glaze
NY
7 Gersley Borate
3 Feldspar Soda
1 Bentonite
1 Iron Oxide Red
(LR 011) (started to rain, did not reach max temperature)
Borax and Talc – brown, blue/green glaze
The wessel exploded, on the fragments, a thick glossy black/green glaze, the lumps/grains come from Borax.
3 part Borax
1 part Talc
1 part Bentonite
4 part Quarts
1/8 part Copper carbonate
(LR 012)
Bone white
8 Borax E Frit P2953.1
2 Talc
1 Bentonite
(LR 013)
Blue/red-brown, spotted, and black glaze
A lot is going on in this glaze, it seems to be dry red when too thin, metallic/crystalline when medium thick, blue, and sometimes metallic when thicker, dark glossy when thick.
3 part Borax
2 part Gerstley Borate
1 part Lithium Carbonate
1 part Talc
1 part Magnesium Carbonate
4 part Quarts
1 part Kaolin
1/2 part Copper carbonate
1/2 part Bentonite
(LR 014) (Reference Campfireglaze 006)
Green, rust, yellow, and brown
Use less flux
2 part Borax
2 part Gersley Borate
1 part Sodium Carbonate (baking soda)
2 part Quartz
1 part Kaolin
1/4 part Copper carbonate
(LR 015)
Strontium – Black glossy hard surface
Runny, not like expected at all, too much flux
4 part Borax
2 part Gersley Borate
1 part Lithium Carbonate
1 part Strontium
2 part Quarts
1 part Bentonite
1/2 part Yellow iron oxide
Also try this wash:
- 4 Gerstley Borate
- 3 Iron Oxide green
- 3 Burned Oker
- 1/2 Quarts