Properties of Crystal Glass

The sparkle and brilliance of crystal glass adds elegance to a home or table setting. True crystal glass gets its highly refractive quality from the addition of lead oxide.

History

English glassmaker George Ravenscroft, the first person to add lead oxide to glass in 1676, gets credit for inventing crystal glass.

Composition

All glass contains silica, but crystal glass contains the lowest percentage of that mineral at about 33 percent. Crystal's lead oxide content ranges from 33 percent to 58 percent.

Features

Lead makes crystal glass soft and easy to cut. The softness can be a challenge to glass makers when they are blowing a crystal glass item.

Solution

To counteract the softness and make working with lead crystal easier, glass makers try to keep the lead oxide content to about one-third. This solution results in less-brilliant glassware.

Considerations

A good way to tell the difference between regular glass and crystal is by sound. Crystal glass emits a light, reverberating ring, while regular glass gives off a brief, dull thud.

References

• Corning Museum of Glass: Glass Chemistry
• Antiques Dynasty: Lead Crystal

Resources

• Glass Manual: All About Glass