A fine, white firing, refractory, kaolinized sand suitable as a body constituent to diversify particle size, add texture, improve drying, and reduce plasticity. This is a unique and quite consistant material mined in Southern Saskatchewan. It is about 60-70% fine 60-80 mesh silica sand and 30-40% clean white plastic kaolin. The raw lump material has an exceptionally clean appearance. We find this material valuable as a body additive to improve drying, to add texture, and to open up the matrix to prevent bloating. Since refractory clays are often too plastic Kaosand is a very useful clean additive that cuts plasticity and maintains the refractory character.

Process Properties

This is a non-plastic material, it cannot be mixed with water and formed by itself. If Kaosand is employed in plastic clay bodies at less than 10% its presence is often barely detectable, even on the potter's wheel.

However in less plastic bodies and in greater amounts its presence will add a a significant sandy texture, increase water splitting in the plastic stage, and increase the generation of slip during throwing.


Test bars made from 50% Kaosand and 50% ball clay; fired to cone 10R (top) and from 7 to 11 oxidation (proceeding downward)

Since Kaosand is high in quartz mineral adding too much to a body may compromise its ability to pass through quartz inversion without cracking in the kiln. However since the quartz particles are quite fine this is normally not a problem as long as less than about 15% is employed.

Kaosand does have some fine iron particles that display as very tiny black specks in oxidation but are larger in reduction.

Physical Properties

 Drying Shrinkage (50% OM4 Ball Clay 21% water): 6.0-7.0%
 Drying Factor: B130
 LOI: 5.5-6.5%
 Dry Density: n/a

Fired Shrinkage (50% OM4 Ball):

   Cone 6: 4.0-5.0%
   Cone 8: 5.0-6.0
  Cone 10: 5.5-6.5

Fired Absorption (50% OM4 Ball):

   Cone 6: 6.5-7.5%
   Cone 8: 3.5-4.5
  Cone 10: 2.5-3.5

Sieve Analysis (Tyler mesh):

     +48 (300 microns): 0-0.1%
   48-65 (300-210 microns): 7.0-13.0
  65-100 (210-149): 23.0-30.0
 100-150 (149-106): 8.0-12.0
 150-200 (106-75): 5.0-10.0
 200-325 (75-45): 5.0-9.0

Safety Data Sheet

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702 Wood Street, Medicine Hat, Alberta T1A 1E9
Phone: 403-527-8535 FAX:403-527-7508