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Colourants - Overview
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Colourants are materials which add colour to a glaze melt other than the effects generated by opacity and light refraction. They could be divided into two groups:

  • oxides such as iron, manganese, nickel, cobalt etc. The chemistry of these oxides can be taken into account in glaze formula calculations.

  • commercially prepared mixtures sometimes called stains. The analysis of these materials is usually not known so we cannot take them into account in glaze formula calculations.

While colourant materials are not usually considered to have a significant effect on the chemistry of the glaze melt in some cases, particularly where quantities are greater, they can have a very important influence on the degree and quality of the melt. e.g. in saturated iron glazes iron oxide might be present in quantities of 10 to 20%. In reduction iron oxide is a vigorous flux (FeO) and will influence the fluidity of the melt. Other colourant oxides such as manganese dioxide and cobalt oxide belong to the flux group but they may only be used in such small quantities that they have little effect in this role in a melt.

Colourants As Seperate Materials

Matrix treats colourants as seperate materials storing them in a special database in the Raw Materials folder. The database file is called Oxide Colourants.col Other colourant database files can be created with different names if you wish. They should always be stored in the Raw Materials folder.

The Colourants Environment

Colourants database is managed in the Colourants environment. To enter the Colourants environment click the Colourants tab in the Matrix Window.

Fig.1 The Colourants Environment

Fig.1 shows the Colourants environment.

Colourant raw materials are listed and the information stored for the highlighted colourant is displayed in various boxes in the window.

The bank of buttons at the bottom of the window initiated processes such as

  • the entry of a new colourant material,
  • the editing of an existing colourant in the database,
  • the deleting of a colourant from the database
  • the creation of a new colourant database
  • the loading of another colouant database if you have created one
  • the saving of a newly entered or edited colourant material.

The Independence of the Colourants Environment

Actions which you perform in the Colourants environment are independent of processes underway in the other environments. For example you may be in the process of entering a recipe in the Recipe to Formula environment and find that a colourant listed in the recipe is not in your database. Yopu may switch over to the Colourants environment, enter the colourant material into your database then switch back to the process of entering the recipe where you left off.

Information Stored with each Colourant in the Database

Name The name of the colourant raw material.
Date Date when the material was entered into the database
Chemical Formula The chemical formula for the raw material. This will be used if colourants are checked to be included in formula calculations.
Oxide Entering Melt The chemical formula for the oxide entering the melt.
Molecular Weight The molecular weight for the raw material.
Cost Cost of the material per kilo. Used in recipe cost calculations.
Abbreviation Needed for recipe charts such as those generated for recipe databases. This is usually the chemical formula for the oxide entering the melt.
Fired Colour - Oxidation A text of maximum size 254 characters to indicate the range of colour which might be expected from the use of the material in oxidation firings.
Fired Colour - Reduction A text of maximum size 254 characters to indicate the range of colour which might be expected from the use of the material in reduction firings.
Comment Any comment you wish to add to the information stored with the material.

Follow these links for more information about:


Overview | Entering & Editing or Deleting Colourant Materials