Magnesium Carbonate

A supplemental source of magnesium oxide for glazes. An excess will cause crawling due to very high fired shrinkage but it can be used to advantage to produce intentional beading or to make lizard skin effects when used on top of a well-bonded base glaze. Other sources of magnesia are dolomite (with calcia) and talc (with silica).

For more information on light magnesium carbonate, see the Digitalfire.com Reference Library  of ceramic materials.