How to Make Lead Glass

Glass consists primarily of a component called a network former that provides the network structure of the glass. It also contains additional components called network modifiers that give the glass specific properties. Lead glass contains lead in the form of lead oxide, which gives lead glass its distinctive brilliance and resonance. Lead glass was first made as early as 1400 B.C., although specific manufacturing processes were not developed until the 1600s.

Things You'll Need

• Cutting wheel
• Glass cutting tools
• Glassblowing pipe
• Glassmaker's furnace
• Molds
• Potash
• Red lead
• Sandstone wheel
• Silica sand

Instructions

1. Obtain sufficient quantities of your ingredients. Lead glass contains 48 percent silica sand, 24 percent potash and 28 percent red lead. Red lead is formally known as lead tetroxide and has the chemical formula Pb3O4.
   Ordinary glass contains about 63 percent silica sand, 22 percent soda and 15 percent limestone.

2. Add the silica sand and potash together and heat in a furnace to a temperature of about 1,200 degrees Celsius. Introduce the red lead with a fast current of air. This process must fully oxidize the lead so that it doesn't leave any metallic lead. Mix these ingredients together to obtain the molten lead glass.

3. Pour the molten glass into molds. This will create the basic shape of the object, since the molten glass begins to harden as soon as it touches the mold. Lead glass is thicker than ordinary glass; it requires a well-coordinated team of artisans to make lead glass of high quality.

4. Shape the glass. The hollow portions of glassware are made by blowing the glass, in a process that has changed little over the past 2,000 years. The solid parts of the glassware are made by shaping the molten glass in one quick motion before the glass hardens. Allow the glass to cool slowly over a period of two to 16 hours.

5. Cut the facets. The glass cutter draws a pattern with red lead and turpentine. A powered cutting wheel then makes the rough design, and the finished facets are made by hand.

References

• How Products Are Made