Egyptian Blue (000164-0030-F-1010)

Overview

Working Notes  

Opalizes upon firing, with potential thin threads of color variation.  

At tack fusing and slumping temperatures, the surface may develop an inconsistent metallic gray film, which typically disappears at full fuse temperatures. To localize this effect, occurring only where Egyptian Blue is exposed, cap or layer with clear glass. Testing is recommended for specific applications. For more consistent results, consider using Steel Blue Opalescent (000146). Refer to "Special Effects: Steel Blue Opalescent" for more details.  

At a full fuse, Egyptian Blue Opalescent may leave trace amounts of copper on the kilnshelf. These deposits can react with sulfur-bearing glasses in subsequent firings. Processes requiring more heatwork, such as pattern or flow bar techniques, may increase copper deposits. These deposits, often invisible, can react even after proper cleaning and repriming of the shelf or replacement of ThinFire. This contamination is temporary and may burn out over subsequent firings. Firing glasses other than sulfur-bearing varieties will prevent reactions. Bullseye notes the highest contamination with sulfur-bearing French Vanilla Opalescent (000137) and Spring Green Opalescent (000126). For burnout firing, Bullseye suggests a 300°F/hr ramp to 1525°F, holding for 1:00.  

Note About Glass Cleaner: The exposed surface of 000164 is more sensitive to glass cleaner. Traces of cleaner may result in a metallic sheen on fired works, especially at tack fusing and slumping temperatures. To avoid this, thoroughly buff the glass with a towel to remove all cleaner before firing. 

Bullseye Compatible.