Fire Clay - High Temperature Mortar Ingredient


Fire Clay, Fireclay, Mortar Clay and/or Bricklayers Clay is an organic material that has been dried and turned into a powder form. It is usually a brackish red / brown in color or it could be white / grey. The texture is like baking flour or baking soda.

These powdered clays can be found at most Masonry and Landscape Supply Stores for about $10 per 50lb bag of firing clay (also see companies below).

You may find a bag of fire clay at a Big Box hardware store like Home Depot, Lowes or Menards - but it’s unlikely. 

If you can’t find a bag near you, check with your local Ceramic / Pottery Supply  - or -  Laguna Clay Distributors and they can order a bag of Fire clay for you (w/out shipping charges).

If all else fails, we can always ship you a bag of Fire Clay - We've got plenty in stock!  But keep in mind - FedEx Ground is expensive, so we begrudgingly have to add that to the cost of the fire clay... 


  • Low Fire Clay - Very Porous / Not Waterproof
  • Mid Fire Clay - Excellent Bonding Properties / Waterproof
  • High Fire Clay - Excellent Bonding Properties / Waterproof 


High-Temperature Mortar Mix Recipe: 

3 Parts Silica Sand
1 Part Quicklime Hydrated Lime
1 Part Fire Clay
1 Part Portland Cement


How to Make High Temperature Mortar

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