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MagnesiumCompounds

 - information regarding use in studio ceramics

• Magnesium Sulphate Heptahydrate, Epsom Salts - Wikipedia
  • Decomposition anhydrous decomposes at 1,124°C, monohydrate decomposes at 200°C, heptahydrate decomposes at 150°C, melts at 714˚C
  • Solubility 71 g/100 mL (20 °C)
  • Majority is used in agriculture
  • Reacts with Sodium Carbonate => Magnesium Carbonate and Sodium Sulphate
  • Reacts with calcium chloride=> Calcium sulphate and Magnesium Chloride
• Magnesium Chloride にがり 卤水 MgCl2?
  • https://en.wikipedia.org/wiki/Magnesium_chloride
  • 54.3 g/100 mL (20 °C), 72.6 g/100 mL (100 °C)
• Magnesium Hydroxide
• Magnesum Acetate Mg(CH3COO?)2
  • https://en.wikipedia.org/wiki/Magnesium_acetate
  • calcium magnesium acetate (CMA) is used as an evironmentaly friendly ice melter.
• Magnesium Carbonate
  • Magnesium Carbonate has a small solubility and is sometimes used to provide flocculation. An excess can be included as the solubility limits its ability to flocculate.
• General considerations. Surfaces caused by Magnesium compounds look very similar to surfaces caused by calcium compounds. Thick Magnesium salt surfaces, in my experience shiver off the clay. Thin ones do not.

These compounds are strong flocculants.

The chlorides in the presence of Barium Carbonate form Barium Chloride. This material is much more hazardous than barium carbonate. These mixtures in my opinion must be avoided unless the people using it have a real understanding of the hazards involved and know how to properly dispose of them.

Both magnesium Sulphate and Calcium chloride have been successfully sprayed into cone 9 vapor firings. The surfaces are what one might expect although the specking of ash does not happen and the fume acts a fume, not like solids that settle from the stream of gases. If you spray much magnesium sulphate in the kiln the surface will shiver. Of course this will also glaze your kiln and shelves.

I am not a safety expert, or a chemist. Do not use this site as a primary source for safety, chemistry or disposal information.

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