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Table 1  Evolution of porcelain pastes used at representative British factories in the eighteenth century.

Table 2  Compositional formulae for selected porcelain paste ingredients.

Table 3 Composition of selected porcelain paste ingredients.

Table 4  Conversion of a mineral formula to a wt.% recipe ingredient.

Table 5  Calculated soapstone paste recipe.

Figure 1  Gew Grange soapstone quarry. (Photo, Victor Owen.)

Figure 2  A view of the bay at the end of the Gew Grange quarry. The pale band in the cliff is a shear zone in which soapstone formed at the expanse of the dark host rock (peridotite). (Photo, Victor Owen.)

Figure 3  Teapot, Lowestoft, ca. 1770. Soft-paste porcelain. H. 6". (Courtesy, Roderick Jellicoe.)

Figure 4  Plate, William Reid, Liverpool, ca. 1757. Soft-paste porcelain. D. 9". (Courtesy, Roderick Jellicoe.)

Figure 5  Coffee can, William Reid, Liverpool, ca. 1758. Soft-paste porcelain. H. 2 1/4". (Courtesy, Roderick Jellicoe.)

Figure 6  Coffee cup, Derby, ca. 1758. Soft-paste porcelain. H. 6". (Courtesy, Roderick Jellicoe.) This enameled example has an unusual ear-shaped handle.

Figure 7  Vase, Derby, ca. 1760. Soft-paste porcelain. H. 6". (Courtesy, Roderick Jellicoe.)

Figure 8  Coffee can, Samuel Gilbody, Liverpool, ca. 1758. Soft-paste porcelain. H. 2 1/2". (Courtesy, Roderick Jellicoe.)

Figure 9  Mug, Samuel Gilbody, Liverpool, ca. 1758. Soft-paste porcelain. H. 3 1/2". (Courtesy, Roderick Jellicoe.)

Figure 10  Breakfast cup, Pennington’s, Liverpool, ca. 1785. Soft-paste porcelain. D. 4 1/2". (Courtesy, Roderick Jellicoe.)

Figure 11  Plate, Bow, ca. 1756. Soft-paste porcelain. D. 8". (Courtesy, Roderick Jellicoe.)

Figure 12  Sauceboat, Worcester, ca. 1754, Soft-paste porcelain. H. 2 3/4". (Courtesy, Victor Owen.)

Figure 13  Identification of eighteenth-century porcelain factories based on bulk alumina contents (Al2O3).

Figure 14  Phase diagram of how porcelain pastes melt in kiln temperatures.

Figure 15  Diagram showing the shape (morpohology) during heating.

Figure 16  Diagram showing crystallized mineral grain.