Contains

Copper

May React With

Selenium, Sulfur, Reactive (000009, 001009, 001019)

Cold Characteristics

Uniform colour.

Working Notes

At tack fusing temperatures, the surface frequently develops a metallic grey film. This usually disappears at full fusing temperatures. To maintain the metallic effect, fire as quickly and low as possible. Dark interface reaction likely with sulfur glasses (for example 001137, 001437, 000137).

At a full fuse, Steel Blue Opalescent has the potential to deposit trace amounts of copper on the surface of the kiln shelf. These deposits may react with sulfur-bearing glasses in subsequent firings. Processes that require a greater network, such as pattern or flow bar techniques, can also lead to copper deposits. Such deposits may not be visible and can react even when the shelf has been properly scraped and reprimed or when ThinFire has been removed and a new ThinFire is applied. This type of contamination is impermanent and may be burned out/fired out throughout subsequent firings. A contaminated shelf can be fired with glasses—other than sulphur-bearing glasses—and no reaction will take place. In our studios, we've observed the greatest contamination in subsequent firings with sulphur-bearing French Vanilla Opalescent (000137) and Spring Green Opalescent (000126). For a burnout firing, we recommend a rate of 300°F/hr to 1525, with a hold of 1:00.