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Description: Andalusite/pyrophyllite/sericite

Oxide Analysis Formula
TiO2 0.50% 0.03
Al2O3 21.00% 1.00
SiO2 73.10% 5.91
Fe2O3 0.40% 0.01
Na2O 1.30% 0.10
K2O 1.30% 0.07
LOI 2.50%n/a
Oxide Weight 474.06
Formula Weight 486.21


Sericite is blended with andalusite/pyrophyllite ore to lower the PCE and produce the Alkatrol series of products. These are added to wall and floor tile to increase fired strength, in stoneware, structural ceramics, coatings, and whiteware ceramics to improve whiteness, widen firing range, reduce warpage, increase thermal shock resistance, and stabilize shrinkage.

This material is manufactured by crushing & screening and dry milling of selectively mined andalusite/pyrophyllite/sericite ores.

Individual alkatrol variations have different chemistries, the one shown here is an average.

Related Information


Materials Andafrac
Materials Pyrofrac 0204
Materials Pyrofrac 0304
Materials Pyrofrac 1004
Materials Pyrofrac 1655
Materials Pyrofrac 1855
Materials Pyrofrac 2023
Materials Pyrofrac 2024
Materials Pyrofrac 2034
Materials Pyrofrac 4203
Materials Pyrofrac 4205
Materials Pyrotrol
Materials Pyrofrac
Materials Pyrophyl
Materials Andalusite
Materials Pyrophyllite
Materials Alkatrol G-20041
Materials Alkatrol W-20031
Materials Alkatrol W-22535
Materials Seriphyl
Typecodes Aluminum Silicate
Materials not classifiable as commonly known aluminum silicates. For example, kaolin is a common aluminum silicate.


Density (Specific Gravity) 2.60
Dry M.O.R. (50% Silica) 398C


Body MaturityAssists in the formation of mullite at lower temperatures than formed by conventional alumina-silica sources.
Body PlasticityModerately high percentages of the Alkatrol products can be substituted in body compositions to reduce laminations in pressing and to aid in extrusion.
Body Thermal ExpansionAdd this to reduce thermal expansion and reduce firing shrinkage.
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