Foundry Hill Creme

Alternate Names: New Foundry Hill Creme, Foundry Hill Cream, Foundary Hill Cream

Description: Plastic clay for stoneware clay bodies

Oxide	Analysis	Formula
CaO	0.50%	0.04
K2O	0.70%	0.04
MgO	0.50%	0.06
Na2O	0.55%	0.04
TiO2	0.50%	0.03
Al2O3	20.50%	1.00
P2O5	0.09%	-
SiO2	66.20%	5.48
Fe2O3	1.60%	0.05
LOI	8.20%	n/a
SO3	0.09%	n/a
Oxide Weight		453.48
Formula Weight		494.47

Notes

Similar to a ball clay but having a much lower drying shrinkage (about 6-6.5%) and more iron (but a distinctly low TiO2). Although this is a fairly refractory clay, it has a high firing shrinkage, around 8% across the entire range from cone 7 to 11. Porosity drops slowly from cone 7 upward (7% down to 4% at cone 11 oxidation and 10 reduction). Used commonly in stoneware clay bodies.

The manufacturer states: An intermediate-grained engineered blend offering excellent moisture retention and plasticity properties. Ideally suited for a wide variety of stoneware applications and wet forming process.

Relative Viscosity (1.2 Sp. Gr.):* 1.28
Casting Rate: (gms per 15 min/426 cm2):* 209
Water of Plasticity:* 22.9
% Dry Shrinkage:* 3.94
Dry M.O.R., psi:* 239

Cone 04 8 11
----
Fired Shrinkage:* 0.2% 1.6% 1.9%
Absorption:* 20.2% 17.8% 15.2%
M.O.R. psi:* 758 2390 4630

Thermal Expansion, Cone 8: .493% at 700C
P.C.E.: 30
pH: 5.9
Oil Absorption: 28
Bulk Density, lbs per cubic foot: 37-45
Particle Size, Microns: 20 10 5 2 1 0.5 0.2
88% 73% 60% 44% 33% 21% 8%

*Specimens: De-aired, extruded, 50% ball clay, 50% flint

Related Information

Original Container bag of Foundry Hill Cream clay

Foundry Hill Creme fired test bars

Top: Cone 10R (soluble salts are staining the surface). Downward: Cone 11-7 oxidation.
These look very similar to a typical ball clay, perhaps not firing quite as white.

Foundry Hill Creme: What is it?

Foundry Hill Creme (FHC) is used in North America as a stoneware body base or addition. It fires like a ball clay, being quite refractory. But it is much less plastic. How much feldspar would it take to make it into a vitreous cone 6 stoneware? We fired SHAB test bars from cone 4 to 10 (bottom to top) and 10R (the soluble salts discolor it in reduction). The data collected (in our Insight-live.com group account) produces firing shrinkage and absorption data that calculates to the red columns (and plots to the blue lines). Notice how the porosity drops steadily from cone 3 to 10 (the firing shrinkage rises steadily over the same period). We mixed it with 20% nepheline syenite and collected the data on that also, that plots to the orange lines. Notice 2200F (cone 6): The added nepheline drops the porosity from 8% to zero (and increases the firing shrinkage about 2%). Notice also the FHC drying shrinkage (the first DSHR red column) averages a little under 6.5%, it is enough to tolerate the non-plastic addition of nepheline syenite and still maintain good plasticity (notice the mix averages a little higher, that is because it was softer).

Links

Typecodes	Clay Other Clays that are not kaolins, ball clays or bentonites. For example, stoneware clays are mixtures of all of the above plus quartz, feldspar, mica and other minerals. There are also many clays that have high plasticity like bentonite but are much different mineralogically.
Materials	Gleason Ball Clay

Data

Pyrometric Cone Equivalent	31

By Tony Hansen
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