All About Glass

All About Glass

This is your resource for exploring various topics in glass: delve deeper with this collection of articles, multimedia, and virtual books all about glass. Content is frequently added to the area, so check back for new items. If you have a topic you'd like to see covered, send us your suggestion. If you have a specific question, Ask a Glass Question at our Rakow Research Library.

Annealing and Tension in Glass

Hot-working processes used to form a glass object—glassblowing for example—must be followed by a very gradual cooling period called annealing. See what happens when an object is not properly annealed and learn why it breaks.

Annealing Glass

If a hot glass object is cooled "too quickly," it may be strained at room temperature, and therefore may break easily. For small, or thin-walled shapes (particularly those made of glasses having low expansions) the effect may not be serious. For more massive pieces, the strain can be very