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Pine Lake Fireclay

Plastic Pennsylvania Fire Clay

Oxide Weight338.13
Formula Weight373.63
If this formula is not unified correctly please contact us.
PCE - Pyrometric Cone Equivalent 29-30
SVWT - Sieve Analysis Wet on 28 mesh: 1% 35 mesh: 6.5% 48 mesh: 9.0% 65 mesh: 8% 100 mesh: 12.5% 150 mesh: 12.0% 200 me

This once popular (but variable) fire clay has not been available for many years. It occurs in many clay body recipes and common substitutes are Hawthorn Bond (likely the best) and AP green fire clay. However this is not a refractory material, it has about the same vired maturity at a typical cone 10 brown iron stoneware (or even more vitreous). Porosity is 2% at cone 10R and 10 oxidation. Fired shrinkage is 5.7% at cone 10. At cone 7 porosity is 4% with 5.2 shrinkage. Drying shrinkage is 5.8%, so this is not a highly plastic material like some fireclays (it has about the plasticity of a typical pottery clay).

Very different chemical analyses have been presented for this material.
For example, another lists SiO2 as 70.8 and Al2O3 and 25.4 with no LOI?

Lignite can be big trouble

Lignite can be big trouble

Example of the lignite particles in a fireclay (Pine Lake) that have been exposed on the rim of a vessel after sponging. This is a coarse clay, but if it were incorporated into a recipe of a stoneware, glaze pinholing would be likey.

Pine Lake fireclay lab test bars

Pine Lake fireclay lab test bars

Fired to cone 10R (top) and 7,8,9,10 oxidation (from bottom to top).

Out Bound Links

By Tony Hansen

XML for Import into INSIGHT

<?xml version="1.0" encoding="UTF-8"?> <material name="Pine Lake Fireclay" descrip="Plastic Pennsylvania Fire Clay" searchkey="" loi="0.00" casnumber="70694-09-6"> <oxides> <oxide symbol="CaO" name="Calcium Oxide, Calcia" status="" percent="0.300" tolerance=""/> <oxide symbol="MgO" name="Magnesium Oxide, Magnesia" status="" percent="0.100" tolerance=""/> <oxide symbol="K2O" name="Potassium Oxide" status="" percent="0.500" tolerance=""/> <oxide symbol="Na2O" name="Sodium Oxide, Soda" status="" percent="0.300" tolerance=""/> <oxide symbol="TiO2" name="Titanium Dioxide, Titania" status="" percent="1.900" tolerance=""/> <oxide symbol="Al2O3" name="Aluminum Oxide, Alumina" status="U" percent="27.300" tolerance=""/> <oxide symbol="SiO2" name="Silicon Dioxide, Silica" status="" percent="58.600" tolerance=""/> <oxide symbol="Fe2O3" name="Iron Oxide, Ferric Oxide" status="" percent="1.500" tolerance=""/> </oxides> <volatiles> <volatile symbol="LOI" name="Loss on Ignition" percent="9.500" tolerance=""/> </volatiles> </material>

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