Over 1500 quality clay and ceramic products for hobbyists,
teachers, and potters.
FAQ
Ceramic Stains
General Information
Only inorganic pigments can be used in ceramic ware. Ceramic
stains are raw oxides and chemicals that are mixed and calcined
(fired) in a furnace at temperatures from 1400 F to 2600F, and
then ground up into a powder. Stains produce colors that can not
be made by simple mixing. Although ceramic stains are generally
very stable colors, they can be sensitive to the make-up of the
glaze, the temperature and the atmosphere in the kiln.
You can use stains to color clays, slips, and glazes. Stains can
be wedged directly into prepared clay. The typical percentages
of color will range from 5-15%. For more even color, stains should
be mixed into the dry clay body before adding water. Stains that
contain zircon (Zr) are generally the most stable.
Prepare underglaze colors by using a combination of stain, kaolin
and flux. An underglaze can contain up to 50% stain, depending
on the depth of color desired. Some flux (usually 2-5% of your
glaze) is required to provide the necessary binder and to help
prevent the glaze from crawling. Ceramic stains are most commonly
used as a source of color in glaze. Additions of 4-8% of dry weight
are typical.
Formulas
**Be sure to run your own tests**
Underglaze Cone 04-10
Frit #3110........30
Ball Clay...........30
Stain.................30
Satin Clear Cone 6
Neph Sy...........60
Strontium..........20
OM4................10
Silica................9
Lithium.............1
Stain................2-12%
Some helpful tips to aid you on your way:
1) Base glazes should contain 12-15% whiting for best results.
2) A pinch of tin oxide may brighten colors.
3) Reduction firing may be detrimental to your color (You may
want to use inclusion stains) .
4) Be wary of free zinc; it may cause a negative effect.
5) Mason stains are rated up to cone 6 (may go higher), and are
more vibrant at lower cones.
6) Keep a log while testing to record how you mixed glazes, and
firing procedures.
7) Online resources: www.masoncolor.com and www.claymaker.com
Safety and Handling
The Material Safety Data Sheets (MSDS) should be read and
understood before handling or using these products. They are available
in our TECH section. If stains are to be used in contact with
food or beverage, the ware should be checked by a testing laboratory
to determine if they meet FDA requirements. Be aware of the following
when using ceramic stains and glazes:
1) Possibly carcinogenic.
2) Harmful if inhaled or ingested.
3) Causes eye irritation.
4) May cause skin irritation.
5) Avoid breathing dust. Use a dust mask or respirator.
6) Avoid contact with eyes, skin, and clothing.
7) Keep container closed.
8) Use with adequate ventilation. Use a dust mask or respirator.
9) Wash thoroughly after handling.
10) Keep away from food.
11) Contain spills or leaks; pick up and place an approved container
for disposal. Dispose of in accordance with federal, state and
local laws.
12) These products are non-reactive and non-flammable.
Copyright 2003 Fort Pottery Company. All rights reserved.
