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2019 Jiggering-Casting Project of Medalta 66 Mug
A cereal bowl jigger mold made using 3D printing
Beer Bottle Master Mold via 3D Printing
Better Porosity Clay for Brown Sugar Savers
Build a kiln monitoring device
Coffee Mug Slip Casting Mold via 3D Printing
Comparing the Melt Fluidity of 16 Frits
Cookie Cutting clay with 3D printed cutters
Evaluating a clay's suitability for use in pottery
Make a mold for 4-gallon stackable calciners
Make Your Own Pyrometric Cones
Making a high quality ceramic tile
Making a Plaster Table
Making Bricks
Making our own kilns posts using a hand extruder
Making your own sieve shaker for slurries
Medalta Ball Pitcher Slip Casting Mold via 3D Printing
Medalta Jug Master Mold Development
Mold Natches
Mother Nature's Porcelain - Plainsman 3B
Nursery plant pot mold via 3D printing
Pie-Crust Mug-Making Method
Plainsman 3D, Mother Nature's Porcelain/Stoneware
Project to Document a Shimpo Jiggering Attachment
Roll, Cut, Pull, Attach Handle-making Method
Slurry Mixing and Dewatering Your Own Clay Body
Testing a New Load of EP Kaolin
Using milk as a glaze


The number of different frits in the world can be intimidating, there are thousands. However, unlike stains, their are a wide range of standard formulations that have been made for many years. We are having difficulty finding and classifying them all and it will be done in time.

Obviously, since color and other fired properties are a product of the chemistry, we need to know the chemistry of the frits we use to fully control and understand them. Actually, if we have the chemistry, all other information is secondary. However many frits have specific chemistries that are the product of an intense research effort to produce a specific result using a specific firing method. To anyone other than the engineers to developed the frit, the chemistry will only seem novel. Such a frit can obviously just be used to supply oxides to a glaze as any other material, but it purpose (and likely its greater cost) would be wasted.

Unfortunately most frit companies either do not publish chemistry information at all (some have in the past but have discontinued) or publish approximate chemistries. Frit manufacturers often do reveal chemistries to individual users. Thus old product literature, books, substitution information, xray diffraction or other means of analysing the chemistry, leaked information from technical people at manufacturers and derivation by comparison of approximate chemistries to standard formulations of other producers are the sources for the numbers provided here. Fast-fire and other special purpose frits are a more recent development and the chemistry of these is more closely guarded. If you have any frit data, please contact us so we can share it. As you can see we do not have advertising on this site, we have always striven to share this type of information with a good motive. In future we will be providing better tools to search for frit substitutes and find frits based on their chemistry.

In the curious world of frits, the websites of most frit producers offer surprisingly little information about their products, generally most of the documentation we have comes from users and authors. Some companies do not even have websites or pages that google can find. Many companies change the names of their products over time, this adds to the complexity of maintaining chemistry info. In addition, suppliers often buy frits from a manufacturer, then rename and sell under their own brand (fortunately often the names bear some resemblance to the original so these can be tracked). Other companies number the same frit differently in different countries. Much of the information about specific frits is wrong or outdated, but we can only use what we have until we can convince the manufacturers to be more open. If the chemistry of a frit is not available here, often there will be a link to an equivalent (keep in mind that links are classified so a link to a substitute is not equivalent to a link to a similar one). Our INSIGHT software has a mechanism for naming a frit one way and using the chemistry of another.

Two key frit properties are the thermal expansion and melting behavior (remember that frits do not melt at a specific temperature but over a range). There are different ways of measuring both of these and we are attempting to document these in the testing section. It is generally more practical only to compare the numbers of products from the same manufacturer.

The particle size of frits is not nearly as important as it is for stains. There is a wide range of qualities of frits available (again quality generally refers to consistent particle dynamics and chemistry). The manufacturers using older equipment and processing methods have greater problems maintaining quality. Other companies have modern equipment but have not fully learned the importance of quality, sometimes a supplier will act as an agent (and even blender) between a manufacturer and users to assure quality.

The production of stains can entail the usage of often toxic materials and money can be saved by taking shortcuts it dealing with wastes. Some manufacturers are taking advantage of less stringent environmental and workplace hazard regulations in third world countries to produce stains cheaper but sometimes with greater human cost to the local people and their land.

Related Information


Tests Frit Fusibility Test
Tests Heating Microscope Analysis for Frits
Tests Glass Transition Temperature
In ceramic glasses (usually frits) the temperature at which the hard brittle state of the glass changes to the rubber-like state that precedes softening and melting
Articles A Low Cost Tester of Glaze Melt Fluidity
This device to measure glaze melt fluidity helps you better understand your glazes and materials and solve all sorts of problems.
Articles The Chemistry, Physics and Manufacturing of Glaze Frits
A detailed discussion of the oxides and their purposes, crystallization, phase separation, thermal expansion, solubility, opacity, matteness, batching, melting.
Articles Glaze Types, Formulation and Application in the Tile Industry
An technical overview of various glaze type used in the tile industry along with consideration of the materials, processes and firing.
Articles Low Budget Testing of Ceramic Glazes
There is more to glazes than their visual character, they have other physical properties like hardness, thermal expansion, leachability, chemistry and they exhibit many defects. Here are some simple tests.
Glossary Frit
Frits are used in ceramic glazes for a wide range of reasons. They are man-made glass powders of controlled chemistry with many advantages over raw materials.
Glossary Boron Frit
Most ceramic glazes contain B2O3 as the main melter. This oxide is supplied by great variety of frits, thousands of which are available around the world.
By Tony Hansen
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