The process begins in the batch room with the basic bulk materials of sand, soda and lime. These materials, along with other alkaline fluxes and stabilizing ingredients, are mixed with various amounts of coloring agents, such as cobalt, manganese, selenium, and cadmium, according to carefully calculated formulas to make the numerous colors offered by Wissmach Glass. The sheets disappear into the annealing lehr where they cool for 35 minutes. When the glass emerges, each sheet is subjected to a rigorous quality inspection, trimmed to standard size and packed into cases containing either 240 or 420 square feet of glass. On an average day, eight to ten different color runs of glass are made.
Some colors are more difficult to manufacture than others.
Developing a new glass color from the idea to the finished product can take from a few weeks to a year or more. Wissmach's inventory currently includes more than 1,000 colors, tints and patterns. The cathedral glass is available in shades ranging from crystal to dark shades of amber, blue, green and red. These colors are produced in 13 different textures including Double Rolled, Hammered, Seedy, Flemish, Figure C, Moss, Dew Drop, Ripple, Florentine, Granite, Cube, Seville, Corella Classic and English Muffle. Opalescent, a mixed glass, is available in two, three, four and five color combinations and in various controlled densities ranging from the very light Streakys to the very dense.