Magnesium Sulphate

About

• Also known as Epsom Salts
• Used to flocculate (gel) glazes to assist suspension and application to relatively vitreous biscuit ware 
• Usually only about 0.1% is needed, but up to 0.5% can be used with particularly troublesome slurries

Instructions for use:-

• Make up a saturated solution (~30gm per 100ml water)
• Add gradually to the glaze slop 2.5-5ml at a time, stirring well after each addition.
• Continue until you see the gelling occur.

Technical notes:

Epsom Salts work by flocculating the clay content of a glaze. The lower the clay content, the less effective the flocculant.  To improve efficacy, add 2% bentonite. In glazes which are self-deflocculating (ones containing high alkali frit, large amounts of soda feldspar or nepheline syenite) much larger additions of Epsom salts are required to overcome the self-deflocculation.

Further reading on the Digitalfire website>

Collections

• Basic Materials

Ask a Technical Question