The ancient glass industry was divided into two categories: glass making, and glass working (1). Glass making workshops were usually situated near places where the raw materials were available. The materials needed to make glass include sand, nitrate, and lots of heat. To fuse the ingredients together, a kiln must be heated up to a temperature of 1100 degrees fahrenheit. This was accomplished with large amounts of wood for burning, and a strong breeze to provide enough oxygen for the fire (2).
The color and fabric of the glass depended upon the levels of natural metals in the sand. A small amount of iron caused glass to turn green. Manganese could have created yellowish or purple glass. It is uncertain what was used to produce blue glass, but Romans probably utilized cobalt or copper. If a glassmaker desired colorless glass, he could add a neutralizing agent (3).
Once the ingredients were melted together, they created molten glass. This substa…