The Manufacture and Use of Frits

The Cosmetic Jar in the Form of the God Bes and the Shawabty of Ankh-hor were made using the same manufacturing technique as the Shawabty of Nectanebo II, however, their paste recipes are notably different. Both pastes contain ground colored frit in appreciable amounts. Frits are pigmented glassy powders made by melting silica with colorants and suitable fluxes; the resulting glassy material is cooled and crushed. Therefore, the blue coloration of the Cosmetic Jar in the Form of the God Bes and the Shawabty of Ankh-hor is due to the added frit and not to a separate glaze layer. Both Egyptian blue and Egyptian green were frits manufactured in ancient Egypt using the same raw material-sand-and manufacturing processes already developed for faience manufacture. The ancient Egyptians could make a range of materials with different physical or visual properties using the same raw materials in different proportions.
For instance, by taking silica and adding proportionately more calcium and copper and less salt than for faience they produced a blue, matte material that we now call Egyptian blue. Egyptian blue is a granular frit consisting primarily of blue crystals of the synthetic mineral curprorivatite (CaCuSi4010) formed from the raw materials during firing. Egyptian blue was used to create beautiful objects with the appearance of turquoise or lapis lazuli, and was ground and mixed with glue to make paint. Its use as a pigment dates to the time of the pyramids.
Unlike objects made from faience, objects made from Egyptian blue were not glazed. Nonetheless, a range of colors and surface glosses could be achieved. For instance the color of an object could be altered by choosing the color and fineness of the ground frit or by mixing it deliberately with silica to lighten the hue. The pale blue color of the Cosmetic Jar in the Form of the God Bes was achieved by mixing ground silica with ground Egyptian blue; it exhibits a matte surface because the paste contains little glass. Like faience, Egyptian blue bodies can contain differing amounts of glass when fired. The paste used to make the Shawabty of Ankh-hor contains more glass, giving it a burnished, stone-like surface reminiscent of turquoise. Its distinctive pale green color is the result of grinding a greener frit as material for its manufacture. These greener frits, referred to as Egyptian green when used as a pigment, consist primarily of the mineral wollastonie (CaSi03) with lesser amounts of curprorivatite. They form during firing when higher proportions of lime are present.
	Cosmetic Jar in the Form of the God Bes This jar was made from a matte quartz paste colored by Egyptian blue frit. The jar has decorative accents in matte red and yellow quartz pastes colored by iron and lead-antimony compounds respectively.
	It was probably molded in sections that were joined using excess paste. However, extensive refinement of the surface after molding has removed most evidence of this procedure. Examination of Xero-radiographs suggests that the vessel was molded in at least four sections.
	A horizontal seam and an abrupt change in wall thickness below the face is visible in radiographs-corresponding to an area of smeared paste visible on the interior of the vessel. It is likely that the face and body were each molded in two sections that probably corresponded to the front and reverse. The ears appear to have been added separately.
Much of the surface bears evidence of smoothing, modeling, and incising, which would have taken place after molding and assembly. Fine linear details were incised with a tool; and circular depressions, such as the belly button were formed by piercing the paste with a rounded tool. The red and yellow pastes were applied as thin veneers to the finished surface prior to firing. The interior of the jar is covered with dirt; however, a small scraping was analyzed and was found to contain fragments of kohl, a finely ground powder used as a cosmetic in ancient Egypt.
	The Shawabty of Ankh-Hor This shawabty was made from a vitreous paste composed largely of fine angular particles of Egyptian blue/Egyptian green frits held together after firing by significant amounts of glass. It is pale turquoise in color with a relatively matte gloss. The high level of finish has removed many traces of its manufacture; however, it was undoubtedly molded followed by extensive working of the surface to sharpen facial features and create linear and recessed details such as the hieroglyphic inscription. Circular depressions were formed by impressing a tool into the dampened paste.

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