Thomas

Thomas clay is similar to Volunteer clay and has established an excellent history of performance in stoneware and low fire (talc base) plastic and casting formulas. The diverse combination of clays provide enhanced plasticity to a ceramic composition through increased particle packing density. Thomas clay has very good fired brightness and oxidation qualities.

Typical Data Sheet
Shipping Point: Gleason, Tennessee
RAW PROPERTIES  
Crude Color Light Brown 
Dry Modulus of Rupture (psi)* 510 
Wet Sieve Residue, +200 mesh (%) 0.53 
Water of Plasticity (%) 34 
Linear Drying Shrinkage (%) 6.8
Soluble Sulfates (ppm) 190
Filtration (ml) 27 
Specific Surface Area (m2/g) 21.7
CEC/MBI (meq/100 ml) 7.7
pH 5.3 
Particle Size (% less than)
5 Micron
1 Micron
.5 Micron 

86
65
54 
Median Particle Diameter (Micron) 0.47
Carbon 0.25
Sulfur 263

*50% clay/50% flint, cast bars

CHEMICAL ANALYSIS
Silicon Dioxide (SiO2) 56.34
Aluminum Oxide (Al2O3) 27.95
Iron (Ferric) Oxide (Fe2O3) 1.10 
Titanium Dioxide (TiO2) 1.97
Calcium Oxide (CaO) 0.11 
Magnesium Oxide (MgO) 0.33 
Sodium Oxide (Na2O) 0.08 
Potassium Oxide (K2O) 0.46 
Loss on Ignition 9.56

 

FIRED PROPERTIES Cone 04 Cone 3 Cone 11
Linear Fired Shrinkage (%) 5.7 6.6 8.1
Absorption (%) 15.7 10.6 3.6
PCE…………………………….31

NOTICE: All data given and statements and recommendations made herein are based upon our research and are believed to be accurate typical data. However, no guarantee of their accuracy is made or implied. Our products are sold on the condition that the user will evaluate them himself, as well as our formulas and recommendations, to determine their suitability for his own purposes before adoption on a commercial scale. Also, statements as to the use of our products are not to be construed for their use in the infringement of any patent.

Warning: This clay product contains quartz which may cause delayed respiratory disease (silicosis) if inhaled over a prolonged period of time. Avoid breathing dust. Use NIOSH/MSHA approved respirators where TLV for crystalline quartz is exceeded. IARC Monograph Volume 68, 1997 concludes that the respirable fraction of crystalline quartz, causes cancer in humans. Refer to MSDS for complete details.