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Albany Slip

High iron silty low melting clay

Alternate Names: New York Slip, Albany Clay

OxideAnalysisFormula
CaO5.81%0.476
MgO2.71%0.309
K2O3.20%0.156
Na2O0.80%0.059
TiO20.40%0.023
Al2O314.63%0.659
SiO257.82%4.420
Fe2O35.21%0.150
LOI9.41
Oxide Weight416.11
Formula Weight459.33
If this formula is not unified correctly please contact us.
GSPT - Frit Softening Point 1170C
SVWT - Sieve Analysis Wet on 60 mesh: 0 on 120 mesh: 1.0% on 200 mesh: 5%

Albany was a low plastic silty clay that was mined in Albany, New York for many decades. It melts to a glossy chocolate brown glaze at cone 8-10. It was a very popular glaze ingredient for dark colors and tenmoku and iron crystal effects. In the early 20th century it was used extensively on heavy utilitiarian stoneware across North America and even on electrical insulators. Glazes could be formulated very easily using this material as a starting point since it was already balanced and had good slurry properties. Potters especially adopted this material and it appears in thousands of recipes used across North America.

There are a number of substitutes for Albany and anyone with ceramic chemistry calculation software can easily speculate on a mix of materials that matches the chemistry on paper. However keep in mind that judging the similarity to Albany is a complex issue of mineralogy, physical properties and chemistry and it depends on the reliability of the information at hand on what Albany actually was.

Richard Willis

A clay-rich earth, named for its mining location near Albany, New York, USA.  Albany is a glacial clay, popular as a mid-fire hydrous alumino-silicate earth rich in alkalies and irons. Perhaps more popular as a slip for engobes or casting (owing to its relatively low-shrinkage character) than for wheel-throwing or hand-building, it is popularly added in small proportions to enhance most any glaze's or clay's viscosity. Similar products are mined around the world, and some claiming to be "substitutes" include the "Alberta" and "Jasper" slips.

Lithium, albany glaze at cone 5 using original albany slip

Melt fluidity of Albany Slip vs. Alberta Slip at cone 10R

Melt fluidity of Albany Slip vs. Alberta Slip at cone 10R

Albany Slip was a pure mined material, Alberta Slip is a recipe of mined materials and refined minerals designed to have the same chemistry, firing behavior and raw physical appearance.

Albany Slip DFAC dried disk

Albany Slip DFAC dried disk

This shows the soluble salts in the material and the characteristic cracking pattern of a low plasticity clay. Notice the edges have peeled badly during cutting, this is characteristic of very low plasticity.

90:10 Albany:Frit and Alberta:Frit comparison

90:10 Albany:Frit and Alberta:Frit comparison

These are three runs of Alberta Slip being compared with the original Albany Slip. These are ten-gram balls fired on porcelain tiles at cone 6. This test shows how the material flows, how much gases of decomposition it generates and how well it allows them to escape. As you can see, they are very similar in melting behavior.

Out Bound Links

In Bound Links


By Tony Hansen

XML for Import into INSIGHT

<?xml version="1.0" encoding="UTF-8"?> <material name="Albany Slip" descrip="High iron silty low melting clay" searchkey="New York Slip, Albany Clay" loi="0.00" casnumber="70694-09-6"> <oxides> <oxide symbol="CaO" name="Calcium Oxide, Calcia" status="" percent="5.810" tolerance=""/> <oxide symbol="MgO" name="Magnesium Oxide, Magnesia" status="" percent="2.710" tolerance=""/> <oxide symbol="K2O" name="Potassium Oxide" status="" percent="3.200" tolerance=""/> <oxide symbol="Na2O" name="Sodium Oxide, Soda" status="" percent="0.800" tolerance=""/> <oxide symbol="TiO2" name="Titanium Dioxide, Titania" status="" percent="0.400" tolerance=""/> <oxide symbol="Al2O3" name="Aluminum Oxide, Alumina" status="" percent="14.630" tolerance=""/> <oxide symbol="SiO2" name="Silicon Dioxide, Silica" status="" percent="57.820" tolerance=""/> <oxide symbol="Fe2O3" name="Iron Oxide, Ferric Oxide" status="" percent="5.210" tolerance=""/> </oxides> <volatiles> <volatile symbol="LOI" name="Loss on Ignition" percent="9.410" tolerance=""/> </volatiles> </material>


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