All About Blown Glass

Blown glass ornaments hanging
  • 1-80 hours
  • Intermediate
  • 0-2,000

When you think of glass, you probably think of window panes or other flat surfaces first, but ignoring blown glass is an oversight you should consider.

Glass blowing can be used for many purposes, and produce many different finished products. Whether you need to decorate, or use a functional object, blown glass could be the perfect option.

What follows should leave you with a better understanding of the techniques and purposes of glass blowing.

History of Blown Glass

glass blowing

Though the technology involved has advanced considerably since then, people have been making blown glass for over 2000 years. Originally, the only technique available was known as free blowing.

This technique involved attaching a piece of refined, but still molten glass to the end of a clay tube. The glass blower would then slowly blow through the tube, shaping the molten glass around a bubble of air.

Eventually, the glass would cool down, holding the shape it was made into by the air pocket. While free blowing is a very simple technique, it is possible to vary the shapes it produces greatly.

By rotating the piece of glass while it is still soft, its own weight can cause it to change shape, leading to many possibilities.

How Does Glass Blowing Work?

Today, glass blowing is quite different than when it was first invented. While the general principle remains the same, a great many more techniques are now available due to advances in technology.

First, molten glass is created in a furnace. Next, it is transferred to a second furnace known as a "glory hole" where it is cooled slightly, but held at a consistent temperature that allows it to be worked on.

Finally, the glass is cooled very slowly in a third furnace called a "lehr." This technique prevents the glass from cracking.

Uses of Blown Glass

blowing glass

There are many different ways that blown glass is commonly used. Some ways are functional, designed to create a specific useful object.

Others are purely decorative, with no other purpose than to add aesthetic value to the surrounding area. Of course, many functional objects are designed to be of artistic value as well.

Many functional objects, such as bowls and vases, are made from blown glass. It is easy to see why this is the case. Their round shapes are perfectly suited to being, effectively, a solidified bubble.

However, despite the reason why certain objects are obvious choices for things to make out of blown glass, there is a great deal of variety in the shape and appearance of these bowls and vases.

This is particularly true once you factor in the colors they can come in.

Additionally, it is important to consider purely decorative objects. While there are many decorative spherical objects, it is important to remember glass remains flexible and can be worked on with a variety of tools before it hardens.

Because of this, there are many objects of almost any shape made of blown glass. Chandeliers, decorative conversation pieces, and ornaments are all common.

If you can imagine it, chances are someone has made it out of blown glass.