Today we are working with the color OPAL WHITE. These sculpture parts are for a private commission, which will be installed later this week.
Colorants: There are several ways to impart color into glass. Most color is created by mixing a specific oxide into the batch and allowing it to react with the other constituents during the melting process. The results depend on a good number of variables, some of which you have control over and some of which you don’t. Most glassblowers today use a pre-manufactured form of concentrated color that is compatible with the clear glass that they are melting in their furnace. These “pigments” are specifically formulated for applications in hot glass. The colors come in every color of the rainbow, either are transparent or opaque.
Color is manufactured into rod, frit and powdered forms, and can be applied in a million different ways (or more). That’s the fun part. We get color from “Reichenbach”, “Kugler” and “Zimmermanni” in Germany, “Gaffer” from New Zealand and “Flying Colors” out of New Mexico just to name few (they are the glassblower’s version of “Crayola” crayons).
Opacifiers: You can add fluorides (CaF2) and phosphates (Ca3(PO4)2) to opacify the melt. Opal glass falls into this category. Fluorine or Fluorspar is used to make white glass. The fumes are toxic, so adequate ventilation must be provided when melting this color.