Materials

Iron Oxide Red

Red iron oxide is ferric oxide, ground fine enough to give an even colour with no specks. The colour it gives depends on the amount and on the kiln atmosphere.

Copper Oxide Red

Red copper oxide is cuprous oxide, and it has more copper per gram than any other copper addition we stock. It colours glazes and slips like the other two copper additions.

Zircopax

Zircopax is milled zircon, and a common way to make a glaze white and opaque. The particles stay suspended in the glass instead of dissolving, and they scatter the light.

Copper Oxide Black

Black copper oxide is the more concentrated of the two commonest copper additions, with more copper per gram than the carbonate. It colours glazes and slips.

Yellow Ochre is an iron-bearing colourant for ceramic slips, engobes, glazes and clay bodies. It can produce warm earthy colours, with the fired result depending on the formulation and firing conditions.

Tin Oxide

Tin oxide is the opacifier that turns a glaze white. Part of it dissolves into the melt, so the whiteness depends on the rest of the recipe.

Cobalt Oxide

Cobalt oxide is a black powder that fires blue, and it is the more concentrated of the two cobalt powders. It colours glazes, slips and clay bodies.

Titanium Dioxide

Titanium dioxide dissolves into a glaze melt and crystallizes again as the kiln cools. The amount decides whether it variegates a surface or whitens it.

Silicon Carbide

Silicon carbide is a synthetic grit that reduces a glaze from the inside. A very small amount brings copper reds out of an electric kiln, and more of it blows the surface open into craters.

Cobalt Carbonate

Cobalt carbonate is the usual source of blue in pottery, and cobalt is the strongest of the colouring oxides, so a very small addition is enough. It colours glazes, slips, engobes and clay bodies.

Rutile Granular

Granular rutile is a milled natural mineral, almost all titania with small amounts of iron and other metals. The grains are coarse enough to survive the firing instead of dissolving into it.

Chrome Oxide

Chrome oxide is a strong green colouring oxide for glazes and slips. A trace is enough to read as green, and it is also the raw material behind many commercial green and pink stains.

Rutile Ceramic Powder

Ceramic Rutile is a natural titanium mineral, calcined and milled to a fine powder. It disperses through a glaze melt, and it changes the texture of a glaze surface more than its colour.

Silverline Talc

Talc is a hydrated magnesium silicate, and the softest mineral on the Mohs hardness scale. It is the main flux in many low fire white bodies, and in a glaze it is one of the main ways magnesia is added.

CMC Gum

Gum CMC is a cellulose gum that thickens a glaze and binds the dried layer to the pot. It makes a glaze brushable and lets a second coat be applied without lifting the first.

Cryolite

Cryolite is sodium aluminium fluoride, an insoluble source of soda that melts at a very low temperature. It is used in glazes, frits and enamels in small additions.